Hello, my problem is that when I try to run itemupgrade.exe, the weidu screen will show up for half a second then disappear.
I looked at the debug file, and this is what it says:
WeiDU v 21900 Log

C:\Games\Baldurs Gate II\setup-itemupgrade.exe
version = 22900
Newest WeiDU is version 22900, updating!
WeiDU files in version order:
[setup-widescreen.exe] version 22900
[Setup-Valen.exe] version 22900
[SETUP-UB.exe] version 22900
[setup-turnabout.exe] version 22900
[Setup-Solaufein.exe] version 22900
[setup-Oversight.exe] version 22900
[Setup-LongerRoad.exe] version 22900
[setup-bg2fixpack.exe] version 22900
[Setup-Ascension.exe] version 22900
[setup-itemupgrade.exe] version 21900
[setup-widescreen.exe] loaded, 685056 bytes
Copying [setup-widescreen.exe] -> [setup-itemupgrade.exe]: false

This is now happening to every new mod I try to install, help is much appreciated

Thank you very much.

No problem. I've no idea what causes WeiDU to loop during auto-update (something OS related, probably) but I had the same issue quite often.