Sony PCG-GRS100 - Manual (Page 122)

VAIO Computer Quick Start
122
❑ You may not be able to use some PC Cards or some functions of the PC Card
with this computer. Check the guide that came with your PC Card for more
information on its use.
Why does an exclamation mark (!) appear on the Device Manager tab in the
System Properties dialog box?
You may not be using the most recent driver software provided by the PC Card
manufacturer. Make sure the necessary drivers are installed. You may need to
remove the driver software, and reinstall it.