When you get an error message that the pr20master.dat (or other DAT) file is locked or the program is unable to read or write to it, there has been an interruption of, or conflict with, the TaxAct program. This could be caused by security software, Windows rights and permissions, conflicts with user accounts, or different versions of Windows on a network.
Normally, you should be able to:
If the program opens successfully, you can exit Task Manager. If you get the same error again, repeat the steps above (from #2 if you have Task Manager open), reboot your computer (shut down and restart), then open TaxAct.
If the DAT file that is locked is one with a long string of random letters and numbers, you do not have to reboot. With Windows Explorer, go to the Client Data folder and delete this file.
If the above doesn't work, and you still get the error, something else is grabbing the file, perhaps security software. Check your security software information for how to allow the operation of TaxAct. In the meantime, you may have to disable the security software.
If you have TaxAct networked, you may need to end all processes on every computer that is currently connected and sharing the Client Data folder. This will require going to each computer and using the steps above. You may need to shut down each of the computers. If you have a host computer (you are not using a dedicated server), do all the steps on it last, including rebooting.
Network setups that can contribute to this problem:
Make sure you have installed the TaxAct program on each computer you are using and that you are only sharing the Client Data folder. If you are using a dedicated server, use only a folder for the Client Data to share with the computers. Do not share the program executable file (EXE) by running it off the server for all machines.
Make sure you do not have more than one user account logged on to any one computer with the program open at the same time.
All TaxAct processes must be ended with Task Manager. With Windows Explorer, navigate to the Client Data folder, delete the file.
The program will import preparer master information from a previous year if you have it.