Blackberry won't boot. Returns multiple errors

[eric1024]

I just got my blackberry 7290 from ebay about a week ago. So far I've upgraded the OS and installed opera mini. It was working fine until today. I've been searching the internet for solutions.

I've tried taking the battery out and doing a hard reset. This doesn't do any good.

I've tried connecting it to the computer with the battery out, starting the application installer and connecting as soon as it says usb-pin, but it NEVER connects. It either stops at "connecting to the device" or it returns the screen saying it can't connect. The longest I've waited at the "connecting to the device" screen is 3 minutes before giving up.

I've tried using JL_cmder to do a factory reset but it can't connect. I've also tried completely wiping it with JL_cmder but it doesn't connect.

Basically, I would figure that if I can get it connected to the computer I can use the application loader to reset it. The problem is, I can't connect it to the computer.

The errors it gives me are
SWI exception
Device Error 377
Sometimes it will give me a black battery icon with a black line through it. This only happens when the battery is removed and it's connected to the computer or an external power source.
Any thoughts?

[ezrunner]

Wirelessly posted (blackberry 8140)

Go into FAQ and follow directions for what to do when JL_CMDER won't connect

[eric1024]

That just brings me to the application loader. The loader itself will not connect to the phone either. Is there a way I can connect to the phone with a serial port or something and just connect to the data side of it? That way I could manually replace the corrupted files.

[king2049]

Change a use-port,or change a data cable?
maybe some problems with your PC, re-install destop manager (I suggest lower version）
or try in another PC.