Note: The following instructions apply to AppDynamics version 4.4.x on a Windows Server 2012 64-Bit or Windows Server 2012 R2 64-Bit.
There are two methods to solve this issue. No matter which method is used, the user is putting their password into the computer's registry in a way that can be read by anyone with access to this system. AppDynamics does not recommend reusing account passwords. Please use a password specific to this system only.
Method One: use the free Microsoft Sysinternals utility called Autologon.exe which can be found at:
https://docs.microsoft.com/en-us/sysinternals/downloads/autologon The easiest way to use this tool is to double-click on the executable, fill in the necessary information (user, domain, password) in the dialog box and hit Enable. Users can also use the program from the command line, but they have to take care to properly escape any special characters that might be present in their user's password.
However, this information can change slightly depending on which version of Windows being used. The Autologon.exe method does the registry edit changes in the background for you, so it is considered the better of the two options.
Note: In case of agent crash, reboot the server to trigger the auto login and startagent.bat file.