Mail Client Freezing

I have a curious problem. 99% of the time my Notes mail client operates as you would expect. Randomly however, if you create a new memo, enter the address then the subject and then click into the memo body the whole thing stops responding. Similarly if you try to reply it seems to refresh half the screen then just hangs. You’re left having to Ctrl-Alt-Del to clear it BUT, the only way I’ve found to fix it is to reinstall the whole client. It then works OK for a few days before doing it again.Is there a solution to this because I’m going round the twist with uninstalling then reinstalling all the time.

Thanks

AM