We were experiencing this intermittently on one of our Windows 7 desktops. We called VMware Support and their suggestion was to uninstall the agent, uninstall vmware tools, then re-install both. It wasn't really affecting the performance of the one particular desktop for us though, so we just left it alone; just annoying to have a massive event log. It actually eventually just stopped occurring.
If you're using a lot of Windows 7 desktops, I'd suggest upgrading to View 4.5. Win7 is now fully supported, and from our short experience with the upgrade, Windows 7 does seem to behave much better in the latest version.
Blog: http://blog.eeg3.net