I have just upgraded exchange 2010 SP1 to SP3, and had no issues during the installation. However, over the past few days users have had isues with creating mailboxes. "Load balancing failed to find a valid mailbox database."
On diagnosing this issue, I realised ther server has been using more RAM than usual after the upgrade. Now the RAM usage peaks at 97% on average. Restarting IIS was able to release some memory and the issue went away.
My question now is has anyone had such issues and also what could make store.exe use so much RAM.