Thank you for your advice. In this case, we were using
the video driver which came with the card. Because the
error I mentioned doesn't occur very often (but it is
anyway annoying when it happens), we can (after we have
updated the video driver) just wait and see if the error
will occur again. I hope it won't. :)

We are planning to update VFP to version 7.0 in the near
future (and skip the version 6.0). Is there any difference
between the old and newer versions of FoxPro, regarding
these errors?