Home network - PCs unable to connect after the Win10 2004 update

I have a simple home network for my 2 PCs connected by CAT6 cable to the same router. File share for some folders is enabled and access to this has been working perfectly.

... Until the Version 2004 update was done last week on both PCs.

Now I get an error - it cant connect to that drive. None of my shortcuts work.
If I go to File Explorer and type the ip address it brings up a "Windows Security - Enter network credentials" box. No idea what these are - didnt think I had initially setup credentials.


Not even sure where to start troubleshooting.

I pinged each PC in a command prompt which works fine.

Any advice on where to start looking for the issue? What could this upgrade have done?

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larrens said:

...File share for some folders is enabled and access to this has been working perfectly.
... Until the Version 2004 update was done last week on both PCs.

Any Feature Update such as updating to 2004 resets a few things back to their defaults. For simple file sharing it is common practice to turn off Password Protected Sharing. This will have been turned back on by the feature update.

If you had it turned off before you'll have to turn it off again. It's Password Protected Sharing that prompts for those credentials.

Turn On or Off Password Protected Sharing in Windows 10