There are a couple error messages that have raised their heads at odd times as I've set about putting the T809 to use. Here are a couple of them, along with what I have learned about getting around them.
Bluetooth Activate Error. This one is a bit of a drag. I've seen other folks complain of this on the net. I make use of bluetooth both for syncing with outlook and for occasionally using a wireless headset. I went months without this showing up, but suddenly one day when I went to turn on bluetooth, there it came up: bluetooth activate error. And wouldn't let me turn on bluetooth. Someone on an online forum said "this happens when the phone is not fully charged. So not only charge the phone but also try activating while the charger is connected. This didn't work, and neither did taking out the battery. The only thing that resolved this one for me: Waiting a day or two and trying again. Because later on when I tried, it started bluetooth fine. Another possiblity is finding whatever "master reset" command is in the phone. I could imagine that would work but it would likely nuke my settings and maybe my contacts list. So that's the best I can do on that one.
"Not Allowed" error when going in to your SD memory chip. This one is easier. Let's say I remove my microSD memory chip from the phone, perhaps to put it into my computer and plunk a movie on there. Then say I put the chip back into the phone. And I navigate to go look at the contents of the memory chip (keyboard shortcut Menu, 6, 1, 6). And it gives a Not Allowed error. Whaaat? Did my memory get nuked? No, it's just that if you remove and then put the memory back into the phone, you have to turn the phone off and on again in order to navigate in there.
Content Not Supported error when trying to watch one of your movies. This one pops up sometimes when I'm trying to watch a movie that I imported to the phone, but which isn't quite to the specifications that the phone needs -- it's the correct format (mp4 or 3gp) but either its bitrate, frame rate, or something is wrong with the file -- OR, the file is just too damn big (say something like 140 megs, at which point many of my movies start to choke. I just chalk this error up along with the other symptoms of a "movie not converted correctly." Check out the full movie converting and viewing instructions and read them carefully about the configuration and file/movie size.