Patrick I'm not sure what you mean? Context search? Do you mean doing a search will trigger an AV scan?
To confirm, these PST's are not attached to Outlook, they are for archive purposes. But I know some of them have dormant malware (normally trivial old school things, before the days that these were always detected). I was after a way of finding the emails with these and getting rid of them, to reduce the risk of future detection that may corrupt the PST files.