Can't install apps to my 7520

I have googled to no end, tried different versions of BDM, and no matter what I do I always get this message when trying to install apps:

Unspecified error encountered [J:0x0000000A]

I don't have any web services, so I can't do OTA. I have to use BDM. What is going on? I have the latest OS, 4.1.0.380, and the latest BDM for this Blackberry, 4.3. I was able to update the OS, and I can sync with Outlook, but I can't install apps.

My boss gave me this as an 'upgrade' to an old i710 phone, so I am trying to make the best of it. Any help most appreciated.

Are you sure the application you are trying to download is for your specific device and OS? It sounds like it isnt. There arent that many apps that are for your OS. What exactly are you trying to install?

BBText2IM from the BB Geeks Store. It says all I need is OS 4.1, and it says it works with the 7520.

You cant get any apps to load using the app loader or is it just this one. Here is what the blackberry developers say about it. BlackBerry Support Community Forums - Unspecified error encountered [J:0x0000000A] - Java Development - BlackBerry Support Community Forums
What I would try to do is uninstall desktop manager 4.3 and install 4.5 without media manager. Then reboot the pc and do a battery pull on your device and give it a shot. I will be leaving for a few hours so if you need more help feel free to pin me or email me at [email protected]

OK, I installed 4.5, latest build. The application failed to install, fatal error, but it did not give me an error code this time. What could I be doing wrong?
BDM does work with Vista right?

This device wouldnt happen to be on a company BES with an it policy on it would it?

do a battery pull and see what happens

bUMPPPPPP FOR THE OLD SKEWLER.