Will a SharePoint search crawler cause a real-time AntiVirus scan with Symantec Protection for SharePoint Servers 5.1/6.0?
Yes, a SharePoint search crawl can cause a real-time AV scan if scanning on downloading is enabled. Though note that if scanning on uploads is enabled and the AV definitions the file was last scanned with have not changed the document will not get scanned if the crawler requests it.
SharePoint 2010/MOSS 2007
Symantec Protection for SharePoint Servers 5.1/6.0