I had now with the current beta several times the problem that the scheme compare was started, but nothing else happened. Also no error message.
You can change the tabs in the toad and continue to work there, but the schema compare does not continue to run and you cannot abort it.
You have to kill the toad with the Task Manager, because it can't be stopped that way.
What does the schema compare show as a status? How far along does it get? Are you sure that it isn't hung on some query?
I just tried it here with the .506 beta, comparing 2 schemas with a few hundred objects each and it worked ok for me.
There is no action on the screen, but you can change the tabs but not close the compare tab.
Its always happen after change the compare destionation
Its always happen after change the compare destionation
I just tried that but still it worked OK for me. Can you give some some precise steps to reproduce it?