Bluetooth connection lost

I have got this Bluettoth dongle which i've been using for 5 years on my old computer with windows xp and had no problems at all.

So now on windows 7, i just plugged in the bluetooth dongle and it installed the drivers and it works the same way as on xp, but i cant transfers files, like long ones such as 2mb, i sent a 200kb file with no problems, but it fails to transfer 2mb files.

This is on my mobile phone i sending from, onto computer.

What shall i do?

Pentium® Dual Core CPU E6500 @2.93GHz (2 CPUs), ~2.9GHz
2.00 GB RAM
32-bit Windows 7
Intel® G41 Express Chipset

Broadcom Bluetooth 2.0+EDR USB Dongle