So, just got my 9800 and am using it on the T-Mobile network. SMS and Emails working great - yes, I have a data plan and its fully provisioned...
I am trying to log into both Facebook and Twitter (pre-installed versions) and both say they are unavailable. I tried both while on EDGE and WiFi, same thing.
I was able to install and use both Flixster and Google Maps flawlessly, if that helps.
I don't know offhand. Did you use the switch device wizard to move to the 9800 from another blackberry, or did you start from scratch with he 9800?
You should try a hard reset first. With the power on, remove the battery for at least 30 seconds. Then try again.
If you used the switch device wizard and the battery pull didn't fix it, you could try deleting those apps, download and install them again, and then try to log in again. I don't know if that is the solution, but it won't hurt.
Sorry guys, yes, I have a Blackberry Data Plan. I had a 9700 plan before and just switched devices on the T-Mobile website. I still cannot get Facebook to work, nor MMS.