ERROR
When opening ArcPad, a similar message as seen below is received and, depending on the type of customizations made to the applet, can prevent ArcPad from opening successfully.
A custom applet (.apa) and / or custom script file (like a VBScript .vbs file) were deleted from the Applets folder directory.
C:\Program Files (x86)\ArcGIS\ArcPad10.2\Applets
C:\Users\[UserProfile]\AppData\Local\VirtualStore\Program Files (x86)\ArcGIS\ArcPad10.2\Applets
Get help from ArcGIS experts
Download the Esri Support App