I created a project in Stardraw Design 7.0 (I'm not sure if it's relevant that it was 7.0). Now today I tried to open it and although I am signed in (and updated to 7.1) I'm getting the message "You do not have permission to open this file. Contact the owner or an administrator to obtain permission."

I believe I am the owner and administrator! Any help very much appreciated.

I tried attaching it to an email and it I get the same message again about not having permission. I could try Dropbox?

Dropbox would be fine.

Kind regards,
Rob Robinson
Stardraw.com

Can't upload it to DropBox, I don't have permission.

Google Drive is the same

Since any file operation using any application causes the same message it is safe to assume that this is a file or system issue. 
Please see http://support.microsoft.com/kb/2623670/en-us#method12 and related topics. 

Kind regards,
Rob Robinson
Stardraw.com

For those following the thread, Ajay72 solved the problem - which was a Windows file ownership/permission issue - by using a free third party utility which reset the permissions on every file on his PC.  This took a while, but it solved the problem which appears to be unrelated to Stardraw Design 7.

Kind regards,
Rob Robinson
Stardraw.com