IMP-11 MP3 Player - doesn't show on computer

Hi! My sister has got an iitronics IMP-11 MP3 player for her birthday. However, I am having trouble getting it to install. I have installed the driver that came with it and that is now listed on "my programs".However when I plug the MP3 player in with or without supplied cable no "removable disk" is shown on "my computer". I have delved into the "system" and the "Universal serial bus controllers" and there is a "USB 2.0 (FS) ADFU Device". I double click this and it says it is working properly. However, when I go on Windows Media Player 10 no device is detected! I have looked at other posts on these forums and can't find the relevant help.
Please can someone help?