# How to Fix QuickBooks Error 6073 (and 99001): Multi-User Fix Guide Operating QuickBooks Desktop in a multi-user environment enables accountants, billing specialists, and inventory managers to collaborate on a single general ledger simultaneously. However, when database locks fail to clear or file hosting permissions fall out of sync, your workflow can grind to an abrupt halt with QuickBooks Error (-6073, -99001).  This error is one of the most frustrating roadblocks for growing businesses because it locks team members out of the company file, often during critical billing or payroll cycles. Written from the perspective of QuickBooks ProAdvisors and database system specialists, this comprehensive guide explains the technical causes of Error 6073, reviews real-world business scenarios, provides verified step-by-step solutions, and outlines preventive protocols to protect your accounting data. ## What Is QuickBooks Error 6073? [QuickBooks Error 6073](https://dataserviceteam.com/quickbooks-error-6073/) is a database-level access conflict that appears when a workstation attempts to open a company file (.QBW), but the QuickBooks Database Server Manager detects that the file is already locked by another process, opened in Single-User Mode, or placed in a read-only state. **When this error occurs, QuickBooks displays one of the following diagnostic messages**: "QuickBooks is unable to open this company file. It may have been opened by another user. You should ask that user to switch to multi-user mode so you can both use it at the same time. The error code is (-6073, -99001)." Or: "QuickBooks is trying to open the company file in an environment that is read-only or restricted." flowchart TD User["Workstation Requests Company File Access"] --> LockCheck{"Database Lock Evaluation"} LockCheck -->|File Open in Single-User Mode| Err["Trigger Error (-6073, -99001)"] LockCheck -->|Active Network Locks (.TLG / .ND)| Err LockCheck -->|Folder Permissions Read-Only| Err LockCheck -->|Multi-User Clear & Host Verified| Open["Grant Multi-User Access (.QBW)"] ## Primary Causes of QuickBooks Error 6073 and 99001 Error 6073 is rarely caused by damage to your underlying transactions; instead, it is almost always triggered by file-system locks, network protocol conflicts, or user configuration states: * **Company File Open in Single-User Mode**: Another user or an automated background integration logged into the company file in Single-User Mode, preventing concurrent access across the network. * **Orphaned Database Lock Files**: A workstation crashed, disconnected from Wi-Fi, or shut down improperly, leaving lingering Network Data (.ND) or Transaction Log (.TLG) lock files active on the server. * **Read-Only Folder or File Attributes**: The shared network folder storing the company file or the .QBW file itself is set to "Read-only," which blocks the database engine from creating temporary write handles. * **Active Cloud Sync or Backup Interference**: An automated backup utility, anti-virus scanner, or cloud service (such as Dropbox, OneDrive, or Google Drive) is actively scanning and locking the file in the background. * **Corrupted Network Data Configuration**: The .ND file has become corrupted or contains outdated IP pointers, causing the host machine to block incoming workstation requests. * **Inadequate Windows Sharing Permissions**: The Windows user account on the workstation does not have full read, write, and modify permissions for the shared host directory. ## Real-World Business Scenario: The Unexpected Payroll Lockout 1. **The Situation**: A mid-sized distribution company operates with six workstations accessing QuickBooks Desktop Enterprise hosted on a local Windows Server. On Thursday afternoon, the payroll manager was processing payroll checks in Single-User Mode to maintain exclusive access during tax calculations. Due to a power surge, the payroll manager's PC abruptly rebooted before they could switch the file back to [Multi-User Mode](https://dataserviceteam.com/quickbooks-multi-user-mode-not-working/). 1. **The Breakdown**: When the accounts receivable clerk attempted to record incoming payments ten minutes later, their terminal halted with Error (-6073, -99001). Although the payroll manager's workstation was turned off, the host server's Sybase database engine still registered the file as locked in exclusive Single-User Mode by that user's session token. 1. **The Solution**: The IT administrator navigated to the host server, opened Task Manager to terminate lingering background database handles, renamed the orphaned .ND configuration file, and used the QuickBooks Database Server Manager to perform a clean rescan. Normal multi-user operations resumed within minutes without any loss of payroll data. ## Pre-Troubleshooting Checklist: Protecting Your Accounting Data Before modifying network sharing permissions or restarting server services, complete these preparatory checks: * **Create an Immediate Manual Backup**: If you can access the file from the host computer or any workstation in single-user mode, generate a local backup (.QBB) via File > Back Up Company > Create Local Backup. * **Confirm Network File Storage**: Verify that the company file is hosted on a supported local server or host computer running [QuickBooks Database Server Manager](https://dataserviceteam.com/quickbooks-database-server-manager/), rather than a network-attached storage (NAS) device that does not support full Windows file-locking protocols. * **Pause Cloud Synchronization**: Ensure the folder containing your .QBW file is completely excluded from active synchronization services such as OneDrive, Box, or Dropbox. ## Step-by-Step Solutions to Fix QuickBooks Error 6073 Follow these troubleshooting procedures in order, moving from simple user-mode checks to server-level configuration fixes.  ### Step 1: Check If the File Is Open in Single-User Mode The most common reason for Error 6073 is that another user has opened the file in Single-User Mode. * Walk to the other computers on your network or ask team members to check their QuickBooks screen. * If any user has the company file open, have them click on the File menu at the top left. * Look at the menu options: * If the option says Switch to Multi-User Mode, click it. * If the user is running an administrative task (such as rebuilding data or running payroll), allow them to finish, then have them switch to multi-user mode. * If a user was logged in on a machine that crashed or shut down, turn that computer on, open QuickBooks, and close the file properly via File > Close Company/Logoff. * Return to the affected workstation and attempt to open the company file. ### Step 2: Terminate Lingering QuickBooks Background Processes If a workstation lost connection unexpectedly, its background tasks might still be holding database locks on the host. 1. On the workstation showing the error (and on the machine that last had the file open), press Ctrl + Shift + Esc to launch the Windows Task Manager. 1. Click the Processes or Details tab. 1. Look for the following background processes: * QBW32.EXE * qbupdate.exe * QBDBMgrN.exe 1. If any of these processes are running while QuickBooks appears closed on the desktop, select each one and click End Task. 1. Repeat this check on the host server if no users are actively working in QuickBooks. ### Step 3: Remove Read-Only File and Folder Attributes If the folder or file attributes were changed to read-only during an operating system update or backup routine, QuickBooks cannot create the required lock files. * On the host computer or server, open Windows File Explorer. * Navigate to the directory where your company file is stored (e.g., C:\Users\Public\Documents\Intuit\QuickBooks\Company Files). * Right-click the folder containing your company file and select Properties. * On the General tab, look at the Attributes section at the bottom. * If the Read-only checkbox is marked or filled, uncheck it. * Click Apply. In the confirmation dialog, choose Apply changes to this folder, subfolders and files, then click OK. * Next, right-click the actual company file (.QBW), select Properties, confirm that Read-only is unchecked, and click OK. ### Step 4: Rename Corrupted Network Data (.ND) and Transaction Log (.TLG) Files The .ND and .TLG files manage network handshakes and transaction sequencing. If they retain obsolete lock states from an improper shutdown, renaming them forces QuickBooks to rebuild clean lock tokens. Note: Renaming the .TLG file will not delete your accounting history; it simply resets the current transaction cache. Your primary data resides in the .QBW file. Ensure all users have completely closed QuickBooks Desktop. On the host server, open the folder where your company file is located. Locate the files sharing your company file's name but with the extensions .ND and .TLG: * Example: CompanyFileName.qbw.nd * Example: CompanyFileName.qbw.tlg Right-click the .ND file and select Rename. Add .OLD to the end of the filename: CompanyFileName.qbw.nd.OLD. Right-click the .TLG file, select Rename, and add .OLD: CompanyFileName.qbw.tlg.OLD. Open the QuickBooks Database Server Manager from the Windows Start menu. Click the Scan Folders tab, browse to your company file folder, and click Start Scan. Once the scan completes successfully, reopen QuickBooks on your workstation in multi-user mode. ### Step 5: Run QuickBooks Tool Hub (File Doctor & Quick Fix) If manual steps do not clear the lock, use the official diagnostic tools bundled in the QuickBooks Tool Hub: * Close QuickBooks Desktop on the workstation experiencing the issue. * Launch the [QuickBooks Tool Hub](https://www.scenario.press/blogs/529394/Download-QuickBooks-Tool-Hub-Latest-Version-1-6-0-8) (ensure you are using the latest version, such as 1.6.0.8). * Select the Program Problems tab on the left. * Click Quick Fix my Program. This routine terminates hanging memory leaks and resets licensing registries. * If Error 6073 persists, switch to the Company File Issues tab. * Click Run [QuickBooks File Doctor](https://dataserviceteam.com/quickbooks-file-doctor/). * Browse to select your company file, choose Check your file and network, enter your administrative password, and initiate the diagnostic repair. ## When to Seek Professional Assistance While Error 6073 is frequently resolved by removing read-only flags or resetting .ND files, certain technical barriers require database intervention: * **Persistent Lockouts with Zero Active Users**: The database engine continues to report the file as opened exclusively even after restarting all workstations and the host server. * **Corrupted Internal Security Tables**: The Sybase SQL database header is damaged, causing the software to misread user counts and multi-user flags permanently. * **Multi-Host Network Disconnects**: Networks running complex virtualized servers (Hyper-V, VMware) or Active Directory Domain Controllers where Group Policies continuously reset folder permissions to read-only. * **Simultaneous -[6000 Series Errors](https://dataserviceteam.com/quickbooks-error-6000-series/)**: Error 6073 accompanied by fatal errors like -6000, -82 or -6123, which point to deeper transactional index table corruption. ### Contact the Data Service Team When standard network steps and automated tools cannot release the file lock or when facing severe multi-user downtime, contact the dedicated Data Service Team at +1-(888)-718-7888 for professional, secure database reconstruction, multi-user network optimization, and comprehensive QuickBooks data recovery. ## How to Prevent QuickBooks Error 6073 1. **Establish Single-User Protocols**: Require team members to notify the office before switching to Single-User Mode and enforce switching back to Multi-User Mode immediately after completing administrative tasks. 1. **Avoid Network-Attached Storage (NAS) Drives**: Host company files only on supported Windows operating systems running the dedicated QuickBooks Database Server Manager utility. 1. **Use Wired Ethernet Connections**: Require all accounting workstations to connect via reliable gigabit Ethernet cables. Sudden Wi-Fi dropouts frequently leave orphaned lock files on the server. 1. **Schedule Proper Shutdown Routines**: Never turn off client computers or the host server with QuickBooks running. Always exit via File > Exit to give the database engine time to release its memory handles. ## Frequently Asked Questions (FAQs) Does Error 6073 mean my company data is corrupted? * No. In the vast majority of cases, Error 6073 is an operational state error rather than structural data corruption. It simply means the database engine has detected an exclusive file lock, a read-only restriction, or an active single-user session. What is the difference between Error 6073 and Error 99001? * They appear together as a paired diagnostic message (-6073, -99001). The 6073 code indicates that QuickBooks cannot access the file due to an existing lock or read-only restriction, while -99001 is the secondary database sub-code indicating an active single-user or hosting conflict. Can I fix Error 6073 by copying the file to my desktop? * Yes, as a diagnostic test. Copying the .QBW file to your local C:\ drive and opening it locally can confirm whether the issue is caused by server network locks or folder permissions. However, you should not continue entering live transactions in the local copy while other users work on the network, or you will create split, out-of-sync ledgers. Why does the error keep returning after renaming the .ND file? * If Error 6073 returns repeatedly, an automated process (such as an anti-virus scanner, an unapproved cloud backup service, or a third-party reporting tool) is likely locking the file in the background, or your Windows user permissions on the host folder are being overwritten by network Group Policy. ## Conclusion & Action Plan QuickBooks Error 6073 and 99001 can disrupt accounting workflows, but it is almost always caused by an active single-user session, read-only folder attributes, or orphaned .ND network lock files. By systematically checking user modes, ending hanging background processes, clearing read-only attributes, and rescanning your folders with the QuickBooks Database Server Manager, you can resolve the lockout and restore multi-user operations safely. If automated diagnostic tools fail to clear the file lock, or if you face persistent database table corruption and multi-user network failures, contact the [Data Service Team](https://dataserviceteam.com/quickbooks-error-6073/) at +1-(888)-718-7888 for immediate, secure database reconstruction, server environment optimization, and complete QuickBooks technical support.