PSA: Cannot open Credentials Manager

I blew several INCREDIBLY frustrating hours trying to troubleshoot issues installing Google Workspace Sync and Microsoft Office 365 on multiple Windows 10 workstations today.

Searching for “failed to create profile” errors when setting up a Google Workspace Sync user for Outlook frequently nets you advice to fire up Windows’ Credential Manager and delete rogue credentials. The same advice often pops up for the dreaded “Trusted Platform Module Has Malfunctioned” error when attempting to register a freshly-downloaded Office 365 application to a user.

Unfortunately, trying to open Credential Manager also fails on affected PCs, with the error “An error occurred while performing this action: 0x80090345.” This was what finally led me to the workaround to the single issue affecting both Office365 setup and Google Workspace Sync setup.

First, open regedit on the affected PC. Then navigate to HKEY_LOCAL_MACHINE\Software\Microsoft\Cryptography\Protect\Providers\df9d8cd0-1501-11d1-8c7a-00c04fc297eb, and create a new registry DWORD value ProtectionPolicy, and set it to 1.

After creating the new DWORD and setting it to 1, restart your PC, and opening Credential Manager should then work fine. Once Credential Manager is open, delete anything you find in there, then register your Office365 apps and/or set up your Google Workspace Sync user.

That was four hours of my life I’m never getting back. Hope you found your answer sooner than I did!