Try creating a new file and then begin merging in your controls and scripts one at a time from the old corrupt file to the newly created one... Worst case scenario you get back most of your work....

I can't open the corrupt file

I know, but can't you open a new file and use the merge function to merge in components from the corrupt file?....

Do you have another copy of your project on the cloud or hard drive?

Ok, made a new file. When I go to merge I can't check any of the boxes - I to merge from other projects too but can't check the boxes.

If you want maybe you can you email me your project and I can see if I can get it merged into a new file?

Email you the file from my C: Drive? Maybe I'm not using the "merge" function properly? I open my new file, click the merge button, open the project I want to merge from, a window comes up with a list of controls with boxes beside them. I click on the little box beside the control and nothing happens. Should the box end up with a check mark in it? Am I doing it correctly?

Yep, ... Should be in My Documents/ARC/My Projects on C Drive... Email it to me and I will have a look...

Ok,I'll do that. Do you think it might help to uninstall and then reinstall ARC?