Abnormally high Outlook 2010 RAM usage for one Terminal Server user (RDS)

I had a user with a very similar issue years ago. The problem was caused by an external calendar. Try removing any/all external calendars.

In Outlook's Calendar Tab:

  1. Record the URLs of any externally hosted calendars
  2. Un-check the box next to any external calendar
  3. Right-click each of those calendars and select "Delete Calendar"

Watch the memory footprint as you remove. If it drops significantly after removing one, you'll know the culprit. Simply re-add the calendars that play nicely.

I don't have sufficient reputation to leave comments yet, so I had to go Jeopardy-style and pose my question in the form of an answer... sorry if this is totally irrelevant.

I can't really explain why, but this issue only happens with a 64-bit edition of Outlook. Downgrading to 32-bit Outlook solves it.