http://www.siemensjobcam.com/windows-mobile-6-1-explorer/
this is about the blackjack ii cellphone/windows vista?
I bought this phone from craiglsist. The dude I bought it from didn’t have a USB cable for it,but I bought one. So,I know to send pics from the comp and so forth,you have to have windows mobile 6.1 installed,after various searching…anyway, I had to uninstall and reinstall the program…it’s actually preconfiguring the folders now or whatever from the usb…but I dont have internet on my phone,nor do I want it right now,but when I tried to install the windows moble 6.1 near the end,it said it couldnt install for internet explorer or something…but my comp still recognizes the phone,which it is installing now…but after about a week of the phone working on the comp with the usb,it stopped….I just want to know what I could do so it wont stop working…and sometimes when I plug the usb in there,it doesnt show the red light meaning its charging…but i hope someone could give some useful info, thanks so much.
First, you DO NOT need to upgrade your BJii to Windows Mobile 6.1 just to transfer files btw your computer and BJii. There are other reasons to upgrade 
but that’s not one of them.
If you are on Vista and your computer is recognizing your phone, you should be able to double click on it and see the folders of your phone. you can copy and paste files from it like any removable drive. If you want you can also use Windows Mobile Device Center 6.1 which you’ll need to install on your computer. Link is below.
If you still want to upgrade, I would recommend restoring the phone to factory defaults (wipe it clean) by holding the directional wheel UP while powering it on and following the on screen directions. THIS WILL DELETE EVERYTHING FROM THE PHONE and put it back to how it was out of the box. Then use the guide on myblackjack2.com to install the upgrade.
Videocast Mobilidades.net – Ep3. Windows Mobile 6.1