There was a fairly detailed process on the old forum that worked without reinstall(I used it on 2 computers) . I understand the old forum is still searcheable but I have lost my link. I am not sure that John's method will cause the change to stick.
Here is what I think the method is. Go to CONTROL PANEL/FOLDER OPTIONS/select tcw or tct file type/select CHANGE/select proper program. Or
go to CONTROL PANEL/FOLDER OPTIONS/select tcw or tct file type/select RESTORE/select ADVANCED/select the proper icon available. There may be other file types associated with TC that you will need to change. Just look for the DoubleCAD icon in the file types.
I think this is the process but as good as my memory is it is sometime very short.
Jon Coxwell, AIA
Windows Win 7x64
TC19,20 32 bit, 20,21,22 64 bit (Platinum)
RedSDK usually off Win 10 pro
Save the Planet
Conserve & Recycle