Warning when saving stylesheet

Hi,

Lately when I edit a style sheet, then go to save it, I get the following warning message:


"Unable to launch. Please be sure that the application exists and that there is enough memory to run it."


I'm running Dreamweaver MX on Windows XP with 512 MB of RAM. I'm not sure, but this may have started when I began creating dynamic pages (php), but it happens no matter what type of page I'm trying to create or edit style sheets on.

Anyone else experience this? Any suggestions?

Thanks for any assistance...