virtualbox.org

I have successfully installed a virtual WinXP 64.
I could use my Logitech LXB Cordless Mouse.

However after I installed the guest additions, when I restarted, the mouse was not installed correctly anymore.
A mousecklick produces now strange results. After some further clicks he mouse does nor react anymore.
I cannot even go to the System to deinstall the mouse driver.

Can I deinstall the Guest Additions again ?

Make sure that the absolute pointer is turned off in the guest additions and DO NOT install the logitech drivers in the guest. If you did remove them.

Sorry, you have to help me further.
I am no expert in using VBOX, therefore I do not know how I can turn off a pointer in the Guest additions.

When I boot the guest I am asked to install a mouse driver. I did not install it as you suggested.

The problem may be that I did not install the WinXP under the guest, but used the program disk2vhd to produce a vhd-file from an existing WinXP installation.

That is exactly the problem. You must un-install the logictech drivers. (on the guest)
start the guest in safe mode and go to the control panel and add remove programs. remove logitech mouse.