Development Profile

Sorry to bring this up again in a new thread.

I had development profiles working for 2 other apps I was working on but now working on a new one and I can’t build to test on the iPhone.
I have read all the past posts and attempted solutions but no luck after 2 days.
I am reluctant to delete everything and start from scratch in case my original apps builds that were working stop as well.

Does anyone have a system to follow?

What does it mean “Could not find Developer Disk Image” when I connect my test iPhone and look at in Xcode Device list?

After bitting the bullet and resetting my Development Identity in Xcode it actually built a new project but when you try and add it to the device you get the above error.

Maybe if someone has a list of all the things I need to delete from keychains and profiles it might be easier to start again… and again…

Go figure deleted everything again today and it wants to work??