Please provide more information regarding the issue that you are experiencing so that I may further assist you.
1. What model phone do you have?
2. Are you receiving an error message when trying to delete an email?
3. Is the phone non-responsive when this happens?
I look forward to assisting you with this issue.
Deleting e-mail with the stock e-mail app (not Gmail) does not work properly for me either. What I did find is that if you move the unwanted mail to the "TRASH" folder it seems to delete it.
Message was edited by: RSPC
Mine works ok for yahoo, I deleted a message from inbox, pressed menu then refresh. when the refresh completed I logged in online and the message was gone. If this is consistently a problem you may want to consider removing and readding the account ( you may want to wait until Yahoo! has restored full IMAP access to all users, some Yahoo! users at this point cannot receive messages when they readd a yahoo account, this mail also apply to ymail/rocketmail domains. I agree that the Email client sometimes does take a while to refresh and times out some of the time, some users find K9 mail improves things, I personally prefer setting up my Hotmail as exchange, because I can set it to push email for when ever, not necessarily 24/7.