When sending messages, I repeatedly get the red X after it tries to send. The error message says "Protocol Error". When this is going on I am also unable to receive messages.

I have checked all the things that it says to check in the troubleshooter and they dont fix anything. I have full reception with the EDGE showing. Every now and then one or two text messages will work and i will get one or two back again before it starts to happen again.

Please help me to figure out the problem.

do you have a SMS plan? even pay per use?

yes, and i checked and i have the most recent os.
Im sending and receiving texts every now and then just fine, but then the error returns.

Call your provider.

any pattern? like to a certain phone # or carrier?

if you do call Cingular wait till Tuesday when the queues are open again

no discernable pattern really...i guess ill just call cingular tuesday. It seems to be working more or less fine now anyways, but if the problem persists ill call them.