I'd like to relay a situation that arose for a customer of mine. It might help someone in the future and perhaps forum members could have some input.
The customer has a mid-2015 MacBook Pro running High Sierra. Customer chooses to use Outlook 2016 for email for one hosted Exchange account and two IMAP accounts. Customer uses Time Machine, with default settings, to backup to an external USB drive that is always connected.
Customer chooses to use "On My Computer" folders for filing/archiving. The resulting main profile is over 40GB.
Last Monday, the customer called me and said that one of the "On My Computer" folders had disappeared along with emails dating back to 2016. Onsite, I confirmed that the folder was not "hiding" in some other place as might be the case if it was accidentally moved or deleted.
After researching the situation I decided that the best course of action would be to restore the Mac via TM to a time when the folder was known to exist, export the folder and its contents, restore the Mac to the last (most current) backup, and import/recreate the missing folder and emails.
With some quirks this worked. However, I discovered what I think are issues with TM and Outlook 2016.
Four of my attempts at a TM restore (and these took up to 2 hours with the slow USB drive) resulted in an Outlook profile that was problematic and could not be rebuilt. It is my theory that the size of the profile combined with ongoing usage of Outlook results in possible corrupted Outlook profiles in TM backups. A backup done without Outlook running would probably be fine.
Getting the old folder and emails back into Outlook's "On My Computer" section was done in the only way I could think of. Outlook has a terrible export function but if you just drag a folder to the desktop it creates an MBOX file. Outlook also has a terrible import function that doesn't import MBOX files. So, I added the Exchange account to Mac Mail, imported the MBOX folder and emails, copied the emails to a folder in the Exchange account, then, in Outlook, copied the emails from the Exchange folder to a new version of the folder in the "On My Computer" section.
One thing I've read about daily Time Machine backups is that they're chosen from the FIRST hourly backup of the day. Why in heck is that?
Last...I'd have to say that if you're someone like my customer that relies on an hourly service technician you might come out ahead if you purchase an SSD for Time Machine.
The customer has a mid-2015 MacBook Pro running High Sierra. Customer chooses to use Outlook 2016 for email for one hosted Exchange account and two IMAP accounts. Customer uses Time Machine, with default settings, to backup to an external USB drive that is always connected.
Customer chooses to use "On My Computer" folders for filing/archiving. The resulting main profile is over 40GB.
Last Monday, the customer called me and said that one of the "On My Computer" folders had disappeared along with emails dating back to 2016. Onsite, I confirmed that the folder was not "hiding" in some other place as might be the case if it was accidentally moved or deleted.
After researching the situation I decided that the best course of action would be to restore the Mac via TM to a time when the folder was known to exist, export the folder and its contents, restore the Mac to the last (most current) backup, and import/recreate the missing folder and emails.
With some quirks this worked. However, I discovered what I think are issues with TM and Outlook 2016.
Four of my attempts at a TM restore (and these took up to 2 hours with the slow USB drive) resulted in an Outlook profile that was problematic and could not be rebuilt. It is my theory that the size of the profile combined with ongoing usage of Outlook results in possible corrupted Outlook profiles in TM backups. A backup done without Outlook running would probably be fine.
Getting the old folder and emails back into Outlook's "On My Computer" section was done in the only way I could think of. Outlook has a terrible export function but if you just drag a folder to the desktop it creates an MBOX file. Outlook also has a terrible import function that doesn't import MBOX files. So, I added the Exchange account to Mac Mail, imported the MBOX folder and emails, copied the emails to a folder in the Exchange account, then, in Outlook, copied the emails from the Exchange folder to a new version of the folder in the "On My Computer" section.
One thing I've read about daily Time Machine backups is that they're chosen from the FIRST hourly backup of the day. Why in heck is that?
Last...I'd have to say that if you're someone like my customer that relies on an hourly service technician you might come out ahead if you purchase an SSD for Time Machine.