BB Curve :: Cannot Sync It To My PC

I was able to successfully update my BlackBerry Curve 3G phone from version 5 to version 6. I love the new version of the BlackBerry OS. I was able to sync it using the BlackBerry Desktop Manager. However recently I'm encountering issues whenever I try to plugin my phone to my computer. Before when I plug it in, I receive a popup that asks me if I am going to charge the phone, sync it or use as a mass storage device. Now, I don't see that message or that popup. It only charges the phone and that's it. The BlackBerry Desktop manager says it's not connected. I even tried connecting the phone via Bluetooth, still no luck. I have tried to uninstall all of the USB devices using the Device Manager as well as installing the USB Drivers from the BlackBerry / RIM website. Still, I can't sync my phone. It just charges it. Btw, I don't see a "BlackBerry" device inside the Device Manager window. I tried using a different laptop, it only charges the phone and I receive a message "USB Device Not recognized." I tried uninstalling the Desktop Manager, USB Drivers fomr the RIM website and uninstalling all of the USB devices. Then after restarting the compute,r I decided to reinstall the Desktop Manager and the USB drivers from the RIM website. Still again, no luck. I can't sync my phone using both computers. Btw, my first computer cannot recognize the phone, it just charges it but it does not show a "USB Device not recognized." message. I'm thinking this issue happened after updating the BlackBerry System Software to a minor version via Desktop Manager. Becuase a few days ago I as able to use it to my computer. It's version 6.0.xxx something. Guys please help me out. I tweeted BlackBerry and they told me to contact my carrier. My Dad bought the phone from Abu Dhabi without any subscription to a specific carrier.