You might want to look at how often you do the inventory scan if you are consitantly getting the out of sync error. But there is no harm in deleting the contents of the Errorscan folder.
If you get a shed-load of out-of-sync's (or Error 2391's in the app event log), you may want to disable "Do Delta" for a week, to force the clients to get back in synch with the Core, and then re-enable it (advanced setting in the inventory service's settings).
If after that it STILL happens, it means that you are loosing inventory scans somewhere in your network, and you may want to notify your network people - maybe a switch is playing up?
- Paul Hoffmann
LANDesk EMEA Technical Lead