BT devices cannot identify my computer (Vista Business)

I'm struggling with a weird problem I suppose.
I'd like to connect my laptop to my cell via BT. Settings on my cell are OK,
still it doesn't identify my laptop.
Trying to set up my laptop always gives an error message when marking "BT
device can detect/identify this computer" under BT 'Options' card. (It may
sound a bit different in the english version, I'm translating ...)
The error (also translated) indicates a problem during saving this setting.
BT device apparently is not connected.

I've no clue what's going on. During starting my laptop the light indicating
BT is active is on. Once I'm logged as a user having administrator rights the
light turns off and of course no icon in the task pane pops up too.

Any hint is very much appreciated. Thanks in advance.


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Markus