M365 - Email auto-deletion policies

[steven_layton_sl]

I have been asked to set up some policies to firm up our auto deletion of deleted emails, so that when a user deletes an email, and then empties the Deleted Items folder, the emails are either no longer kept in that second tier of deletion, or have short retention polciy before they are removed.

I am stuck at the first hurdle, in that I am unsure where to find where the current time periods and rules are set and configured. Where are these rules found in the 365 Admin Console?

[Boredguy]

They were found in the "Classic" Exchange Admin Centre under the Retention Tags and the Retention Policies.

 

You set up the Retention Tag with the name you want, Type as "Deleted Items" and the Retention period you want (we have 30 days)

Then in Retention Policies you can edit your "Default MRM Policy" if you want everyone to have the setting, and add in the new Tag you just created/edited.

 

If you only want it to apply to specific users, you create a new Retention Policy, assign the Tags you want, then you find the user in either old or new Exchange Admin Centre and update their Mail Retention Policy to the suitable one.

[steven_layton_sl]

Hi

The below is taken from my own user. This suggests that I don't have a mail retention policy set against me (and nor will anyone else, I suspect), and so I assume that a default setting will be applied. Is this the case? What are the defaults?

 

[Boredguy]

This is taken from the brand new Tenancy I setup yesterday. By default your users should have the "Default MRM Policy" Applied, and here are the tags and their settings

 

[steven_layton_sl]

How odd, when I check a selection of students and staff, they all do have the "Default MRM Policy" applied to them, and I have only found myself as a user who does not. I have no idea why this is the case.

 

When I look at the content of my Default MRM Policy, it has no tags assigned to it. If all my users are assigned the the "Default MRM Policy" (as it looks like they are), nothing is actually applying to them.

 

[Boredguy]

Someone likely removed the tags previously from it, as they have added 2 additional policies

[steven_layton_sl]

Yes, those two additional policies seem to both be the same, and also seem to match up to how your "Default MRM Policy" is structured.

However, that structure is confusing me, so I wonder if I am not understanding how it works.

Looking at the policy it appears to have far more tags that I'd expect, as they seem to overlap each other. As they are set to differing time periods (1 week, 1 month, 6 months, 1 Year & 5 years), would the policy not always action the tag and retention action with the shortest time period? So only the 1 Week / Delete would occur?

[Boredguy]

The "Personal" type tags, are ones where the user can choose to assign to a folder, it's not enforced, so there are different options so users can select to have stuff go after 7 days, 30 days 365 days etc.

 

"Default" will apply to all folders in the mailbox, and the one one configured would be to move 730 day old messages into the "Archive" folder.

Specific named folders, like "Junk EMail" and "Deleted Items" only apply to those specific folders and none other.

These last 2 types are enforced and users can't adjust it

Edited March 23, 2022 by Boredguy

[steven_layton_sl]

Ah, so in your case all but two of the tags are personal, so users can opt to apply them? The 2 types Junk mail will forably apply to the users Junk folders?

So, am I right in thinking that in your case, using the default, very little is forceably applied?

If I wanted to force auto deletion after x days, I would create a new retention tag based upon a default rule and add that tag to my currently unpopulated "Default MRM Policy"?

 

[Boredguy]

Yes by default on a spanking new tenancy, very little retention is applied to the users mail boxes.

Junk and Deleted are the only things.

 

If you select to create a tag "applied automatically to a default folder" you can then pick from the drop down in the next page which folder exactly that is, if you want to allow it to be recovered from the "Deleted Items" or gone completely, and of course, how old the e-mail has to be before the rule takes effect.

 

Policies can need to wait til overnight for them to take effect after a change

 

Then just add that tag to your policy and sorted

[steven_layton_sl]

I have created this new Retention Tag. The intention is to delete all items from the "Deleted Items Folder" after 7 days, and not allow the deleted items to be moved to the Recorvery area. Is this set up correct? I would then add this Retention Tag to our currently empty "Default MRM Policy" Retention Policy for it to take affect.

 

[Boredguy]

Yep that is setup correctly.

 

Everyone that has the "Default MRM Policy" applied will duely pick it up.

[chaplic]

Any reason you're using the old school RPTs and not the shiny new compliance.microsoft.com ? I should also note that you may surprised how many people 'keep' email in the deleted items..

[Boredguy]

Yep cause I can find them in the old one without them disappearing

[steven_layton_sl]

You might be right about people using the Deleted Items as a form of archive, but we're going to make sure we warn staff.

[Boredguy]

We warned them several times.. and after we had our new retention rules in place for over a year there was still some staff that went "I can't find an email from 14 months ago with details for X that I need".. Not sure which part of "only kept for 12 months" they had forgotten about considering every e-mail says when it will expire