The steps below should resolve the error:
Ensure that all users are out of all HandiSoft programs.
One user will open HandiLedger only. If they use any other programs to open HandiLedger, they need to ensure that they close these programs.
Select the relevant entity. This will display in bold at the top of the window.
Select the Tools menu, and click Rebuild Database files.
Select Entity Details, User reports and Formats, and Standard reports & formats.
Select Rebuild, and agree to the prompts until successful, then click Close.
Have other users re-enter the programs, and the issue should be resolved.