We have this error backing up Exchange CExMAPI::SaveToMessage::SaveToMSG ERROR=MAPI_E_NOT_ENOUGH_MEMORY Detail=Not enough storage is available to complete this operation
Things to try:
- Check there is plenty of free space in the temp folder location. An Exchange mailbox backup will require at least 50% of the mailstore in the temp location as free space.
- Reboot the server because this might be a MAPI memory corruption issue.
- Check the emails shown in the error can be read by Outlook. We have seen instances where corrupt or unreadable emails have caused this error.