QuickBooks Error 6010 100 happens when the program is unable to access your company file because of improper setup, corrupted files, or multiple installs. Opening or working on business files is prohibited by this error. Usually, fixing it entails replacing the.ND file, updating QuickBooks, or modifying firewall settings to restore seamless operation. Our staff of QuickBooks experts can be reached by phone at 1.855.738.2784.