QuickBooks Error Code 6010 100 is typically associated with issues related to the QuickBooks installation process or conflicts with third-party software. It commonly occurs when users try to open a company file, preventing them from accessing their financial data. The error message may read as follows: "QuickBooks Error Code 6010 100: Your QuickBooks installation may have been modified. Try re-installing QuickBooks and then try again."   Solutions to Fix QuickBooks Error Code 6010 100 Disable Antivirus or Firewall

1. Temporarily disable your antivirus or firewall software.
2. Attempt to open QuickBooks and the company file again.
3. If the error does not occur, add QuickBooks as an exception in your security software or adjust the settings to allow QuickBooks to run smoothly.

Run QuickBooks File Doctor

1. Download and install QuickBooks File Doctor, a diagnostic tool provided by Intuit.
2. Launch the tool and select the option to fix the company file.
3. Follow the on-screen instructions to complete the process.
4. Restart QuickBooks and check if the error is resolved.

Rename the QuickBooks Installation Files

1. Close QuickBooks and ensure no QuickBooks-related processes are running.
2. Navigate to the QuickBooks installation folder on your computer.
3. Locate the files with the extensions ".nd" and ".tlg" (e.g., company_file.qbw.nd and company_file.qbw.tlg).
4. Right-click on each file and select "Rename" to change their names (e.g., add ".old" at the end of the file names).
5. Restart QuickBooks and attempt to open the company file again.

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