Mac Mail crashing

Since updating to El Capitan beta version my Mail has caused my iMac to freeze, and I am unable to force quit the application, it also seriously interferes with iTunes and Spotify.
I have tried a reinstall of Snow Leopard and Yosemite to see if this would rectify the problem but sadly it remains so it seems as though it has done something sinister behind the scenes.
Does anyone else have this issue, and how did they get around it?