All, I have a folder that contains old emails that I would like to delete, but I want to insure I am not deleting any folders/files required for the Mail app in Mountain Lion to run properly. The folder is EWS-(my name@my hosted exchange provider), located in Library->Mail->V2-> The EWS folder holds various folders with .mbox suffixes and they in turn hold folders with different messages. What is the EWS folder, and can I delete it? At one point, I tested using the native Mail app w/my exchange provider. Perhaps this is a vestige of that, not sure. Any help would be appreciated.