You want to understand what to do when migrating from a PDQ console running in Server Mode or a PDQ console running in Client Mode to a PDQ console running in Local Mode and you are presented with the following:
In order to switch from Server Mode or Client Mode to Local Mode, you must enter the credentials for the background user used to run the background service in the PDQ Deploy server or the previous background user in the PDQ client, respectively.
For example, if Bob's credentials were the background service credentials used on the PDQ Server console, then the Switch to Local Mode window would ask for Bob's credentials. If Jane's credentials were the background service credentials on the PDQ console prior to migrating to Client Mode, the Switch to Local Mode window would ask for Jane's credentials, even though the PDQ client had been using Bob's credentials.
Deploy: Configuring Central Server
Inventory: Configuring Central Server