Long time Pegasus mail user here, desperate for help: I have the same problem (100% cpu usage) after upgrading to 4.61.
I have seen the suggestions about Load Windows Internet Services, but --- the program sits in the 100% cpu loop before it ever gets to the interface that will allow me to change that setting.
I've tried letting it run for ~2 hours, but that doesn't seem to have accomplished anything. Tried rolling back to 4.51, but that didn't change anything. Tried starting it up with no internet connection, in case it was waiting from something from the net, but that didn't help.
So: is there some file I can edit to accomplish the Options setting noted above, as I can't get to the interface to make the change?
Please help; I've got vast amounts of mail files and Pegasus to date has been wonderful in helping cope.
thanks in advance for any assistance.