[BerryAdict]

via BBForums
BlackBerry Handheld Software v4.6.1.378 (Multilanguage)
From TIM Italy, this OS contains English

Package Version: 4.6.1.378
Consisting of:
Applications: 4.6.1.250
Software Platform: 4.2.0.113
File name: 8900M_PBr4.6.1_rel378_PL4.2.0.113_A4.6.1.250_TIM_I taly.exe
File size: 123.34
Download the OS file here:
https://www.blackberry.com/Downloads...190CAAD5802983

Instructions to install on ANY 8900 from ANY CARRIER.

1. Download the above OS file to the PC then install it to the PC by running (double clicking) the file you downloaded.
2. Go to c:\program files\common files\research in motion\apploader and delete the file named "vendor.xml."
3. Plug in BB and double click on "Loader.exe." It's located in the same place as the above vendor.xml file.

The process takes about 45 minutes to an hour depending on how much data you have to backup and restore during the process. Once it's done loading the new OS it will reboot (it may do this twice during the entire process.) You will see a white screen with an hourglass for up to 20 minutes at a time while the DM says "waiting for initialization."
If, for some reason, you end up with a white screen with small icons and the number 507, simply connect to the PC again and run Loader.exe again and it should load the OS to the device.

For the previous OS version:
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