PSIsafe Management Troubleshooting: Invalid Credentials (L4): Session ID is not a valid GUID

Problem:

Occasionally when accessing PSIsafe Management, and trying to save system settings, or edit user passwords or other areas, you may get the following error:  

Invalid Credentials(L4): Session ID is not a valid GUID; see entry in CheckTokenLog table for details

Solution:

This is due to improper security permissions on the folder, located at:

 C:\Program Files (x86)\CNG\CNGServer

This folder is located on the machine where PSIsafe Server is installed.

Making certain changes within PSIsafe Management updates information in a file located within this directory.  If the security permissions do not allow the contents to be edited, this error will be thrown.

Correct or re-populate the Folder permissions to ensure that users at minimum have Read/Write/Modify permissions to this folder.