It seems likely that your admin attempted to apply a skin to XGUI that had some issues. If he didn't click the "Save Clientside Settings" button, then rejoining the server should have fixed the issue. If he did save the skin file, then he can fix the problem by editing HIS garrysmod\data\ulx\xgui_settings.txt file and finding the "skin" line and replacing it to be: "skin" "Default"OTHERWISE, he could just delete HIS garrysmod\data\ulx\xgui_settings.txt file altogether, then rejoining the server should recreate the file.