I am looking for a solution which would allow to use a convenience of Outlook as a mail client app while at the same time have no PST or OST files on a local computer.
Even in 'non-caching' mode Outlook creates an OST file where it downloads everything from the Exchange server. OWA does not create any local files (except cookies I believe) but lacks some of the nice features Outlook has.
Would it be feasible to place OST files on a network share? Maybe the solution exists for some other client+server pair?
Best Answer
I'm not sure how you're turning off Cached Exchange Mode in your testing, but Outlook 2003 and 2007 will function fine w/o creating an .OST file so long as Cached Exchange Mode is disabled.
Having said that, Cached Exchange Mode is helpful in many circumstances and, typically, doesn't impact the user negatively (since most PCs today have entirely too much local storage). Cached Exchange Mode can reduce server load by decreasing the I/O and CPU resources that users consume on the server (by servicing requests out of their local cache, rather than forcing the server to fulfill user requests).
Placing the Outlook cache on a "network drive" would partially defeat the purpose of the cache (which is to provide fast local access to remotely hosted data).