Every couple of days I notice I have not received an e mail for some time or an e mail or BB messenger message i send does not go thru- when I take the battery out and restart it it works and the e mials go thru. Any solution to this? Thanks

That is the recommended manner to fix it.

How do I reset my BlackBerry? - BlackBerryFAQ

I have performed the hard reset (pulled the battery) but it lasts a couple of days and then the problem comes back.

For some reason your device is losing communications with the tower. You could try a soft-reset instead and see if that does the same for you.

Perhaps you're located in an area that doesn't get very good data coverage.
What is the signal indicator reading before you do the battery pull?

I noticed that it was occuring when I was connected to my wifi at home- could it be that the wifi connection is casuing the issue- since I have disconnected the wifi conenction and use just ATT it has not occured- at least over the last couple of hours - could this be the issue?? Thanks-

See this: Rolling Outages ATT DEC 6th