# TestStand Pop Up "Value Must be at least Zero" When Opened

Updated Dec 2, 2021

• TestStand

## Issue Details

After restarting my PC, when I open NI TestStand, it will pop up a message "The value must be at least zero". How can I solve this issue?

## Solution

You can try the following steps to resolve this error:

• The frontend.dll file might be corrupted. You can resolve this problem by moving this file from another PC with a working install to the corresponding location:
• For 32-bit: C:\Program Files (x86)\National Instruments\TestStand 20XX\Components\Callbacks\FrontEnd\Win32\frontend.dll of this PC.
• For 64-bit: C:\Program Files\National Instruments\TestStand 20XX\Components\Callbacks\FrontEnd\x64\frontend.dll of this PC.
• Backup and delete all files under the directory equivalent to <TestStand_LocalAppData> and then try to launch the Sequence Editor.
• The path mentioned before should be similar to the path C:\Users\<user_name>\AppData\Local\National Instruments\<TestStand Version>.
• When using TestStand 64-bit, you might have to also backup and delete files for NI TestStand 32-bit.
• If the above solutions didn't work, try repairing or reinstalling the NI TestStand software.