Hello [name]! Thanks for joining the GMC. Before making any posts in the Tech Support forum, can we suggest you read the forum rules? These are simple guidelines that we ask you to follow so that you can get the best help possible for your issue.
During an update of Gamemaker I had a powercut and the install didn't finish. I have tried uninstalling, but the uninstall.exe isn't present. Can you tell me how I can uninstall Gamemaker 2 please.
Do a regedit search for the GameMakerStudio.exe and then remove the entry (should be in the HKEY_LOCAL_MACHINE section). If you aren't sure how to go about that, let me know and I'll give more details. Once that's done, re-run the installer and it should work.