Error CodesNetwork

H-Series Errors (H202, H505, etc.)

Updated: October 28, 2025
24 minutes read
13 sections
✓ QuickBooks Desktop 2024✓ QuickBooks Desktop 2023✓ QuickBooks Desktop 2022

Understanding H-Series Errors

QuickBooks H-series errors (H101, H202, H303, H505, etc.) occur when QuickBooks Desktop cannot communicate with the company file stored on another computer or server. These errors prevent multi-user access and are among the most common and frustrating issues in networked QuickBooks environments. The "H" designation indicates "Hosting" or network connectivity problems.

Common H-Series Error Messages

  • H101: Cannot access company file from workstation
  • H202: Company file needs to be updated (cannot communicate with server)
  • H303: Unable to contact the server hosting the company file
  • H505: Connection to company file has been lost
  • H707: Host configuration verification failure

Root Causes

All H-series errors stem from network communication failures between the workstation and server. Common causes include firewall blocking, incorrect hosting settings, Database Server Manager not running, network permissions issues, or damaged network configuration files.

Detailed Error Code Breakdown

Error H101: Cannot Access Company File

Workstation cannot establish initial connection to the company file on the server.

Resolution Steps:
  1. 1.
    Verify Database Server Manager is installed and running on server
  2. 2.
    Check that company file is located in a shared network folder
  3. 3.
    Ensure hosting is enabled only on the server (not workstations)
  4. 4.
    Verify workstation can access the network share (\\ServerName\Share)
  5. 5.
    Check Windows and antivirus firewall settings

Error H202: Company File Needs to be Updated

QuickBooks cannot communicate with the server. Most common H-series error.

Resolution Steps:
  1. 1.
    Delete .ND and .TLG files from company file folder
  2. 2.
    Rescan folders in Database Server Manager
  3. 3.
    Run QuickBooks Connection Diagnostic Tool
  4. 4.
    Verify firewall ports 8019, 56728-56778 are open
  5. 5.
    Ensure all machines use same QuickBooks version

Error H303: Unable to Contact Server

Network connection cannot be established between workstation and server.

Resolution Steps:
  1. 1.
    Ping server from workstation: ping [ServerName]
  2. 2.
    Check network cables and connections
  3. 3.
    Verify server is powered on and connected to network
  4. 4.
    Test accessing shared folders on server (\\ServerName)
  5. 5.
    Disable VPN or proxy connections that may interfere

Error H505: Connection Lost

Network connection was interrupted during QuickBooks session.

Resolution Steps:
  1. 1.
    Check network stability (continuous ping test)
  2. 2.
    Verify server is not entering sleep/hibernation mode
  3. 3.
    Disable power management on network adapters
  4. 4.
    Check for network switch or router issues
  5. 5.
    Update network adapter drivers on both machines

Error H707: Host Configuration Verification Failure

This error indicates that multiple machines are attempting to host the company file, or hosting verification failed.

  • Stop hosting on all workstations (File > Utilities > Stop Hosting Multi-User Access)
  • Enable hosting only on the server where the company file is stored
  • Restart QuickBooks on all machines
  • Delete .ND files and rescan with Database Server Manager

Quick Fix: The 5-Minute Solution

Before diving into advanced troubleshooting, try this rapid fix sequence that resolves 60-70% of H-series errors.

  • 1
    Close QuickBooks everywhere

    Close QuickBooks on ALL computers (server and all workstations). Verify no QBW32.exe processes are running in Task Manager.

  • 2
    Stop hosting on workstations

    On each workstation (NOT the server):

    • Open QuickBooks
    • Go to File > Utilities
    • If you see "Stop Hosting Multi-User Access", click it
    • Close QuickBooks
  • 3
    Delete .ND and .TLG files

    On the server, navigate to the company file folder:

    • Delete CompanyFile.qbw.nd
    • Delete CompanyFile.qbw.tlg
    • Delete any .ND.OLD or .TLG.OLD files
  • 4
    Rescan in Database Server Manager

    On the server:

    1. Open QuickBooks Database Server Manager
    2. Go to "Scan Folders" tab
    3. Select the company file folder
    4. Click "Scan"
    5. Wait for scan to complete
  • 5
    Enable hosting on server

    On the server only:

    • Open QuickBooks and open the company file
    • Go to File > Utilities > Host Multi-User Access (if available)
    • Switch to multi-user mode (File > Switch to Multi-user Mode)
  • 6
    Test from workstation

    Open QuickBooks on a workstation and try to open the company file. If it opens successfully, the issue is resolved.

    • Success Rate

    This quick fix resolves the majority of H-series errors. If your error persists, continue to the comprehensive troubleshooting sections below.

    Solution 1: Verify Database Server Manager

    The QuickBooks Database Server Manager is the core service that enables multi-user access. If it's not installed, not running, or not configured correctly, H-series errors are inevitable.

  • 1
    Check if Database Server Manager is installed

    On the server machine:

    1. Press Windows key
    2. Type "Database Server Manager"
    3. If found, launch it
    4. If not found, you need to install it
  • 2
    Install Database Server Manager

    If not installed, run QuickBooks installer:

    • Insert QuickBooks installation media or download installer
    • Choose "Custom and Network Options"
    • Select: "I'll be using QuickBooks on this computer AND storing company files here"
    • Complete installation and restart
  • 3
    Verify the service is running

    Check Windows Services:

    1. Press Windows + R
    2. Type: services.msc
    3. Find "QuickBooksDBXX" (XX = version year)
    4. Verify Status = "Running"
    5. Verify Startup Type = "Automatic"

    If the service is Stopped, right-click and select "Start". If it fails to start, check Event Viewer for error details (eventvwr.msc > Windows Logs > Application).

  • 4
    Scan company file folders

    Configure Database Server Manager to monitor your company files:

    • Open Database Server Manager
    • Click "Scan Folders" tab
    • Click "Add Folder" and browse to company file location
    • Click "Scan" and wait for completion
    • Verify company files appear with status "Running"

    • Service Not Starting

    If QuickBooks Database Server service won't start, common causes include: corrupted installation, insufficient permissions, port 8019 already in use by another application, or antivirus blocking the service. Try repairing QuickBooks installation via Control Panel > Programs > QuickBooks > Uninstall/Change > Repair.

    Solution 2: Configure Firewall and Open Ports

    Firewall restrictions are the most common cause of H-series errors. QuickBooks requires specific ports to be open on both the server and workstations. Both Windows Firewall and third-party antivirus/firewall software must be configured correctly.

    Required Ports

    • Port 8019 (TCP): Database Server Manager communication
    • Ports 56728-56778 (TCP): Multi-user data exchange (51 ports)
    • Ports 55378-55382 (TCP): QuickBooks Desktop application data
  • 1
    Create Windows Firewall rule for ports

    On the server machine:

    1. Open Windows Defender Firewall
    2. Click "Advanced settings"
    3. Select "Inbound Rules" > "New Rule"
    4. Select "Port" > Next
    5. TCP, Specific ports: 8019,55378-55382,56728-56778
    6. Allow the connection > Next
    7. Check Domain, Private, Public > Next
    8. Name: "QuickBooks Ports" > Finish
     
    Repeat for "Outbound Rules"
  • 2
    Add QuickBooks programs to firewall

    Create program-based firewall rules:

    1. Inbound Rules > New Rule
    2. Select "Program" > Next
    3. Browse to: C:\Program Files\Intuit\QuickBooks [Year]\
    4. Select each file below and create a rule:
       - QBW32.exe (QuickBooks Desktop)
       - QBDBMgrN.exe (Database Manager)
       - QBCFMonitorService.exe (monitoring)
    5. Allow the connection
    6. Repeat for Outbound Rules
  • 3
    Configure third-party firewall/antivirus

    If you use Norton, McAfee, Kaspersky, AVG, Avast, or similar:

    • Add QuickBooks installation folder to exclusions/exceptions
    • Add company file folder to exclusions
    • Add ports 8019, 55378-55382, 56728-56778 to firewall exceptions
    • Temporarily disable the firewall to test if it's the cause

    Antivirus Interference

    Some antivirus programs (especially Norton and McAfee) aggressively block QuickBooks network communication. If H-series errors persist after configuring Windows Firewall, temporarily disable third-party antivirus entirely and test. If this resolves the issue, reconfigure the antivirus with proper exceptions.

  • 4
    Repeat on all workstations

    Apply the same firewall configuration to every workstation that will access QuickBooks in multi-user mode. Firewall rules must be present on both sides of the connection (server and workstation).

    • Solution 3: Use QuickBooks Connection Diagnostic Tool

    The QuickBooks Connection Diagnostic Tool is Intuit's official utility for diagnosing and repairing network connectivity issues. It automatically tests network settings, firewall configuration, Windows components, and QuickBooks services.

  • 1
    Download QuickBooks Tool Hub

    If not already installed:

    • Search "QuickBooks Tool Hub" on Intuit's support website
    • Download QuickBooksToolHub.exe
    • Run the installer and complete setup
  • 2
    Run Connection Diagnostic Tool

    Launch the diagnostic tool:

    1. Open QuickBooks Tool Hub
    2. Select "Network Issues" tab
    3. Click "QuickBooks Connection Diagnostic Tool"
    4. Wait 20-45 minutes (tool runs extensive tests)
    5. Do NOT use the computer during this process
    6. Review results when complete

    What It Tests

    The Connection Diagnostic Tool tests: firewall settings, .NET Framework components, MSXML components, C++ redistributables, QuickBooks services, Windows services, network adapter configuration, DNS resolution, and database connectivity.

  • 3
    Restart and test

    After the tool completes, restart the computer. Then open QuickBooks and attempt to access the company file in multi-user mode. Check if the H-series error is resolved.

  • 4
    Run on all affected machines

    For best results, run the Connection Diagnostic Tool on both the server and all workstations experiencing H-series errors. Run on the server first, then on workstations.

    • Solution 4: Fix Hosting Configuration

    Incorrect hosting configuration is a leading cause of H-series errors, particularly H202 and H707. Only ONE computer should host the company file—the server or workstation where the .QBW file is physically stored.

    Hosting Rule

    Server (where file is stored): Hosting must be ENABLED

    All workstations: Hosting must be DISABLED

  • 1
    Check hosting on server

    On the machine storing the company file:

    • Open QuickBooks and open the company file
    • Go to File > Utilities
    • Should see "Stop Hosting Multi-User Access" (means hosting is ON - correct)
    • If you see "Host Multi-User Access", click it to enable hosting
  • 2
    Disable hosting on all workstations

    On EVERY workstation:

    1. Open QuickBooks
    2. Open (or try to open) the company file
    3. Go to File > Utilities
    4. If you see "Stop Hosting Multi-User Access", click it
    5. Close QuickBooks completely
    6. Reopen and verify "Host Multi-User Access" is shown (do NOT click it)
  • 3
    Use QuickBooks File Doctor

    QuickBooks File Doctor can automatically fix hosting configuration:

    • Open QuickBooks Tool Hub > Company File Issues
    • Click "Run QuickBooks File Doctor"
    • Browse to and select the company file
    • Select "Network connectivity issues" radio button
    • Click "Diagnose File" and follow prompts

    • Multiple Machines Hosting

    If multiple machines are hosting simultaneously, QuickBooks will experience constant H202, H707, or "file in use" errors. This commonly happens after Windows updates or when users open company files from local copies instead of the network location. Always ensure hosting is centralized on the server only.

    Solution 5: Verify Network Permissions

    Insufficient Windows file permissions on the company file or its folder will cause H-series errors. Users need both Share permissions and NTFS Security permissions to access the file over the network.

  • 1
    Configure Share permissions

    On the server, configure folder sharing:

    1. Right-click company file folder
    2. Properties > Sharing tab
    3. Click "Advanced Sharing"
    4. Check "Share this folder"
    5. Click "Permissions" button
    6. Add "Everyone" (or specific users)
    7. Grant "Full Control"
    8. Click Apply > OK
  • 2
    Configure NTFS Security permissions

    Set NTFS permissions on the same folder:

    1. Right-click folder > Properties
    2. Security tab > Edit button
    3. Click "Add" button
    4. Type "Everyone" > Check Names > OK
    5. Select "Everyone"
    6. Check "Full Control" in Allow column
    7. Click Apply > OK
  • 3
    Test network access from workstation

    Verify workstation can access the share:

    1. Open File Explorer on workstation
    2. Type in address bar: \\ServerName\ShareName
    3. Press Enter
    4. You should see the company file folder and .QBW file
    5. Right-click .QBW file > Properties
    6. Verify "Read-only" is NOT checked

    • Domain vs. Workgroup

    In a domain environment, grant permissions to domain user accounts or groups (e.g., DOMAIN\Accounting). In a workgroup, you may need to create matching user accounts with identical usernames and passwords on both server and workstations, or use "Everyone" for simplified permissions.

    Solution 6: Fix Network Configuration

    H-series errors, particularly H303 and H505, often stem from network infrastructure problems. Verifying basic network connectivity and stability is essential.

  • 1
    Test network connectivity with ping

    From a workstation, test connectivity to the server:

    ping ServerName
     
    or
     
    ping ServerIPAddress
     
    Successful result: "Reply from [IP]: bytes=32 time<1ms TTL=128"
    Failed result: "Request timed out" or "Host unreachable"

    If ping fails, the network connection between workstation and server is broken. Check cables, network switches, and router configuration.

  • 2
    Test network stability

    Run continuous ping to check for intermittent drops:

    ping ServerName -t
     
    Watch for several minutes. Look for:
    - "Request timed out" (indicates drops)
    - High response times (>10ms on LAN is concerning)
    - Press Ctrl+C to stop and see statistics

    If you see packet loss or high latency, investigate network hardware (switches, cables, NICs). H505 errors often correlate with unstable network connections.

  • 3
    Check DNS name resolution

    Verify the server name resolves correctly:

    nslookup ServerName
     
    Should return the correct IP address of the server.
    If resolution fails, add server to hosts file or use IP address instead.
  • 4
    Disable power management on network adapters

    Prevent network adapters from sleeping:

    1. Device Manager > Network adapters
    2. Right-click adapter > Properties
    3. Power Management tab
    4. UNCHECK "Allow computer to turn off this device to save power"
    5. Click OK
    6. Repeat on both server and workstations

    Server Sleep Mode

    Ensure the server never enters sleep or hibernation mode. Go to Control Panel > Power Options and set sleep to "Never". Server going to sleep causes H505 errors and file access loss.

  • 5
    Use wired connections

    For reliable multi-user access, always use wired Ethernet connections on the server and workstations. Wi-Fi connections are prone to drops and latency spikes that cause H505 and H303 errors, especially during periods of heavy network traffic.

    • Solution 7: Update and Synchronize QuickBooks Versions

    Version mismatches between the server and workstations can trigger H-series errors. All machines must run the exact same QuickBooks Desktop version and release number.

  • 1
    Check QuickBooks version on each machine

    On each computer:

    1. Open QuickBooks Desktop
    2. Press F2 (or Ctrl+1)
    3. Note the version information at top:
       "QuickBooks Desktop [Edition] 2024 Release R12"
    4. Record edition, year, and release for each machine
    5. Compare - they must all match exactly
  • 2
    Update all machines to latest release

    Update QuickBooks on each machine:

    1. Open QuickBooks
    2. Go to Help > Update QuickBooks Desktop
    3. Click "Update Now" tab
    4. Check "Reset Update" checkbox
    5. Click "Get Updates"
    6. Wait for download to complete
    7. Restart QuickBooks when prompted
    8. Install updates and restart computer if needed
  • 3
    Verify versions match

    After updating all machines, press F2 on each to verify they all show identical version information. Even a minor release difference (e.g., R11 vs. R12) can cause H-series errors.

    • Company File Version

    The company file itself has a version number. If opened with a newer QuickBooks version, the file is upgraded and cannot be accessed by older versions. Press F2 with the file open to see "File Version". All machines must have QuickBooks at or above this version.

    Solution 8: Repair .NET and Windows Components

    QuickBooks relies on specific Windows components, particularly Microsoft .NET Framework, MSXML, and C++ redistributables. Corruption in these components can cause H-series errors.

  • 1
    Run QuickBooks Install Diagnostic Tool

    This tool repairs Windows components:

    1. Close all programs including QuickBooks
    2. Open QuickBooks Tool Hub
    3. Select "Installation Issues" tab
    4. Click "QuickBooks Install Diagnostic Tool"
    5. Wait 10-60 minutes (may take longer)
    6. Restart computer when complete
  • 2
    Manually repair .NET Framework

    If Install Diagnostic Tool doesn't resolve the issue:

    • Download ".NET Framework Repair Tool" from Microsoft
    • Run the tool and follow prompts
    • Restart computer after repair completes
  • 3
    Re-register Windows components

    Run these commands as Administrator in Command Prompt:

    regsvr32 /u qbdmgrn.dll
    regsvr32 qbdmgrn.dll
    regsvr32 /u qbxmlop2.dll
    regsvr32 qbxmlop2.dll
     
    Navigate to QuickBooks folder first:
    cd "C:\Program Files\Intuit\QuickBooks [Year]"
     
    Then run the regsvr32 commands

    • Prevention and Best Practices

    Network Infrastructure

    • ✓Use wired Ethernet: Avoid Wi-Fi for server and primary workstations
    • ✓Quality network equipment: Use business-grade switches and routers, not consumer hardware
    • ✓Stable power: Use UPS (battery backup) for server and network equipment
    • ✓Monitor network health: Periodically test with ping and check for packet loss

    Server Configuration

    • ✓Keep server running 24/7: Disable sleep, hibernation, and automatic restarts
    • ✓Schedule Windows updates: Set updates to install during non-business hours
    • ✓Monitor Database Server Manager: Check weekly that service is running and company files are listed
    • ✓Firewall exceptions: Verify firewall rules persist after Windows updates

    QuickBooks Maintenance

    • ✓Keep versions synchronized: Update all machines simultaneously when new releases are available
    • ✓Single hosting machine: Never enable hosting on multiple machines
    • ✓Use UNC paths: Access company files via \\ServerName\Share\File.qbw instead of mapped drives
    • ✓Regular backups: Maintain daily backups stored off-server

    Advanced: Using IP Addresses Instead of Server Names

    If DNS resolution is unreliable or server names change frequently, you can configure QuickBooks to use the server's IP address instead of its computer name.

  • 1
    Find server IP address

    On the server, open Command Prompt and run:

    ipconfig
     
    Look for "IPv4 Address" under your active network adapter.
    Example: 192.168.1.100
     
    Write this down.
  • 2
    Assign static IP address

    Ensure the server has a static (not DHCP-assigned) IP:

    1. Control Panel > Network and Sharing Center
    2. Change adapter settings
    3. Right-click adapter > Properties
    4. Select "Internet Protocol Version 4 (TCP/IPv4)"
    5. Click Properties
    6. Select "Use the following IP address"
    7. Enter IP address, subnet mask (usually 255.255.255.0), and gateway
    8. Enter DNS servers (often 8.8.8.8 and 8.8.4.4)
    9. Click OK

    Contact IT Administrator

    If your office has managed networking, consult your IT administrator before assigning static IP addresses. Incorrectly configured IPs can cause network conflicts.

  • 3
    Access company file via IP

    From workstations, use IP-based UNC path:

    Instead of: \\ServerName\CompanyFiles\File.qbw
    Use: \\192.168.1.100\CompanyFiles\File.qbw
     
    1. Open QuickBooks
    2. File > Open or Restore Company
    3. Browse and type the IP-based path
    4. Select the company file

    • When to Get Professional Help

    H-series errors can be complex, especially in sophisticated network environments or when multiple solutions have failed.

    Seek Professional IT or QuickBooks Support If:

    • •H-series errors persist after completing all troubleshooting steps
    • •Your network uses VLANs, managed switches, or domain controllers
    • •Database Server Manager service fails to start repeatedly
    • •Errors began after major Windows or network infrastructure changes
    • •You need to migrate QuickBooks to new server hardware
    • •Basic network connectivity tests (ping) consistently fail

    Need Professional Implementation?

    For complex deployments or enterprise implementations requiring expert assistance, GME Inc. provides professional QuickBooks consulting services.

    Contact GME Inc. for Professional Services