To fix the error 'cache write of null page: data\hctjobflow.fat', follow the below steps:
Ensure there is a back up available and all users are closed out of all HandiSoft programs except one user in Practice Manager Contact or HandiSoft.
Go to Tools, then go to Rebuild Database Files.
Select JobFlow Manager Database and JobFlow Manager Archive Database.
Click Rebuild.
Follow the prompts to complete the rebuild.
If the rebuild does not bring back missing jobs, confirm if the jobs are missing for all users, including username Administrator or if it's only affecting one user.
You may need to restore an earlier version of the JobFlow files if the above does not resolve the issue and it's affecting all users.
When there is a backup available, and all users are closed out, navigate to FIle Explorer and then to the HSoft\Data folder.
Rename HctJobFlow.Dat and put today's date on the end after the .Dat.
Rename HctJobFlowArchive.Dat and put today's date on the end.
Restore those 2 files from an earlier working back up.
One user opens Practice Manager Contact as Administrator and follows the steps at the start of the article on rebuilding the JobFlow Manager Database and JobFlow Manager Archive Database again.