Strange Windows Update Issue

[ITGURU]

I've been through all my clients in WSUS to check their all up to date.

 

I've got 1 (so far) that is showing different version (build) to the rest.

 

Machines are in the same room, same hardware, same version of windows.

 

The PC which is up to date is shown below with version, and CU installed. This installed the update ok and shows the updated build.

 

 

Running windows update on the other pc, shows no updates available.

 

If i run the cumulative update manually (same one) I get the error below - update is not applicable. despite showing older build.

 

 

 

 

Any ideas why an update wouldnt be applicable? I've been through the whole WSUS and WU resets, but when try the update again, i still get the same message.