I've been researching this and have read all the posts on it but
nothing has fixed my issue. My CRM works perfectly until we run an
integration which imports leads and creates lead activities, at that
point a few records get integrated but then CRM slows down and
eventually goes the Service Unavailable screen. I reset IIS and
everything is fine again. I don't know where to go at this point in
troubleshooting this any further. I'm confused as to why it only
happens in the integration situation. Manually adding a lead and a
lead activity does not affect CRM the same way as the integration.
Prior to a few weeks ago the integration worked fine and no changes
have been made since that time.