MS Exchange

These are two of the more important folders in Exchange (with MDBDATA being probably the most important).
/MDBDATA is where the Information Store database files are housed. This is essentially all the mailboxes in our Exchange organization and anyPublic folders that may be set up.
/MTADATA contains working directories and files for the Message Transfer Agent (MTA) to be able to queue and deliver messages.
If either of these two folders are deleted or even moved manually (as opposed to being moved through the Exchange Optimizer program), Exchange will cease to function and may not even be recoverable.