Exchange online archive file management help

Copper Contributor

Hi, I hope someone can lend me a hand. I run a computer service company in a very rural area. Most of my customers are home users with the exception for a few businesses I take care of in my area. One of my customers had to upgrade to a new program that had to integrated with Office 365 and using Outlook. This happened in 2017. No problems till now. The archive file on the exchange server is at its limit of 50G and starting to cause mail issues mostly warnings. I have never had reason to learn Exchange since none of my other customers use it and we have not had any problems till now. I am the Exchange Admin and have access to the Admin Center on line. I have had training in a few different programming languages, but trying to follow Microsoft's documentation for access and commands to manage then backup the archive files, lastly to remove it opening the storage space back up. I have a support request but what he sends does not work nor screen shots match.

 SO my question is can someone help me with needed commands or direct me to a complete example of commands to log into the server and then execute the commands to backup these 10 users accounts and then clean them up. If I knew about this file I might have been able to locate a class to learn Exchange server about this maintenance, but seeing it is a problem right now I have to deal with it now and not in 3 to 6 months. Any help is very appreciated.

15 Replies

@NTA-Mark Just to clarify, you mention Exchange and you mention Office 365. They are essentially two different things. When we use the term "Exchange" we are normally referring to a physical on premises server installed and managed by the customer. Exchange Online is Microsoft's cloud service that is managed by Microsoft and is sometimes referred to as "Office 365". I'm going to assume that the user's mailboxes are in Exchange Online (Office 365).

Depending on the licence that your users have, a user can have both a mailbox, and an online archive. Both of these may have size restrictions, again depending on the license. If the user has both a regular mailbox and an online archive, they will see both when connecting via Outlook and via OWA:



This really isn't something that an admin can manage as it's an issue with the amount of data the users are storing in the archive as the size of the archive has exceeded the licensed limit. What the users need to do is open the archive and remove unwanted messages. Having the user remove attachments and storing them in OneDrive may also significantly reduce the archive size. Users can also use the Outlook client to export messages to a file for storage elsewhere, but then you have an issue with where you store that file and the fact that the file may be a security issue (anyone who gets that file can open the messages in it) so it's not something I recommend.

HI Dan,

Thank you for the reply,

Also thank you for the information. Since I have not had to deal with Office 365 and the on line Exchange file in the accounts it is a totally different jungle to navigate.

You are correct. These users have office 365 business standard on their machine and local outlook account and their cloud version on-line. This is what has reached the 50G limit in there standard license. I have been able to use the outlook tools to reduce the size on the local machine, but no way to reduce the on-line server archive file. Thus I was looking to back this file up and then delete it and let it start over.

So you are saying that this can not be done?

How do you edit the on-line archive file to reduce its size?

I need a way to manage this on-line file.

I tried to enter the server using the the shell commands but ran into one error after another in accessing  it. I was tole by Microsoft support I could do this from my exchange admin center but documentation link diagrams are not the same as in my admin center. To me it looks like the older version of admin center where mine was upgraded a little while back. But none of my menus offered the backup option they described.

This is a commercial insurance agency insuring mostly truckers. Lots of documents with PDF attachments. Took 7 years before this on-line archive file to reach its limit but is now causing issues.

Dan it sounds like you know and understand the outlook online archive account. Can you recommend a plan of action I can use to resolve this issue?

Thank you again for your help.



Hi Dan,

I did forget to mention that I did archive folders on the users local machines accounts

 and saved them to their hard disk and a external backup drive.


Hi, I will follow up with this. since this is an insurance agency I can't just delete the mail. Because of leagle reasons and chances that the mail may be needed in a leagle suit I have to be able to recover mail from possible years ago. The reason i just don't flush it.
Perhaps I've misunderstood what your issue is. If you have Business Standard licensing, you get a 50Gb mailbox in Exchange Online. Outlook connects to that mailbox in Exchange Online and caches some (or all) of that data locally to provide a better users experience. There is no "local" file or "Cloud archive" file. The cloud mailbox is the file.

If the mailbox is over 50Gb, then you can enable an Online Archive for the mailbox and users can move data to this separate but related mailbox (this can be automated with policies as well). This will give the user an additional 50GB of storage space. The other options is to remove data from the mailbox. You can do this by using the Outlook client to export some messages to PST (you can Google how to do this) or the user can delete messages from their mailbox. If you export to PST you're then left with an issue of how you securely manage these files, so I'd strongly recommend you don't go down this path.
My recommendation is to elevate your licensing to Business Premium, which includes eDiscovery. This allows you to create retention policies so that when users delete messages, they are retained in the tenant. In the event of a legal incident, compliance managers can search and export this data using eDiscovery (please don't think that retention of data is a most definitely isn't! You can purchase 3rd party services if you want to backup your data).
Hope this helps
Hi Dan,
Thanks again for the help. I guess what is confusing me is when I use the Outlook tools and go to the mailbox clean up. When I click view Mailbox size I have 2 tabs One says local data the other says server The server tab holds these large files. That is what I am trying to backup and remove or make smaller in size.
Forget using that tool. It's not really relevant for cloud based mailboxes. Remember that the local file is just a cache of the mailbox which resides in Exchange Online, and it's the mailbox that is over the limit. The only way to reduce the size of the mailbox is to remove items (ie messages, attachments, calendar entries) from it, and as an admin I wouldn't be deleting items from a mailbox on behalf of users, so generally you put it back on them by saying "'ve paid for 50Gb of mailbox size and you've reached that limit...please delete some mail" (BTW...50Gb is quite a large mailbox...I work with some large enterprises and they don't have anywhere near that for most of their users). If they don't like it, get them to pay for higher level licenses where they get 100Gb mailboxes or look into archiving and/or retention as I talked about previously.
HI Dan,
Thank you again for taking the time to help me understand how their mail system works. It is a bit misleading when you look at the tool. Think you are doing one thing and it really is not having much effect. To alleviate some of the issue sending/receiving mail I Exported Different folders to pst then deleted mail in those folders. Helped a little but not for long. Security is not much of an issue being mostly family members working there.
This is a 7 year accumulation on these accounts. And I'm guessing %85 have PDF and photo attachments, times more than a 100 pages so they can eat up some space. I have looked into adding to 100G. requires them to move up to an E3 license about double a seat from what they are paying now. So we were seeing if arching the online file then cleaning it up was an option. This is were the Tool was giving me the impression this could be done.
Now with your explanation it sounds like it is not possible. You mention there are 3rd party companies that can create retrievable archives of these accounts?
I was playing with my account, don't want to experiment on their accounts but my account in their company has the same issue so it good to work on. When I look at the different folders lest say SENT. I see mail back about 6 month then at the bottom you can click "view more on Microsoft Exchange". Is this where the excess must be removed? I tried a small amount to delete, seemed to remove them. When I tag a large amount down to the bottom of the list it produces an error stating not enough resources or memory close programs and try again. Errors every time. Can you confirm this is where the files need to be deleted?
I can tell you how much I appreciate to taking the time to explain this to me. Been working on computers since the days of DOS and the 5.25" floppy boot disk. Hottest machine on the horizon was a 286 processor and if you sprang for the big bucks you could get a 10MB hard disk (yes 10 megabyte). In all my time I never had to work with office outlook. Word, Excel, occasionally Power point but never Outlook. This company switch to it because another program they switch to required it. Before that they were on my web hosting and mail server. Piece of cake to manage and I did not have to learn a foreign language to work with it. LOL
I am going to discuss the license upgrade again but I'll need to know how to clean them up if they still decline. You have been a wealth of knowledge. Thank you again.
All good...happy to help. It might be easier to use OWA rather than the Outlook client when cleaning up. This connects directly to the mailbox. As I said before, the Outlook client works on a cached copy of the cloud based mailbox (hence the "view more on Microsoft Exchange" when you reach the limit of mail cached locally). My recommendation is to enable the Microsoft online archive natively in EXO. Business basic and Standard provides 50Gb of additional archive mailbox storage, while Business Premium provides 1.5Tb (see this link for details Details on how to enable the online archive for a user are here:
Once it's enabled, users can move items from their primary mailbox to an archive mailbox.
HI Dan,
I do appreciate it very much. I have confidence them to go with the Bus. Prem. upgrade. They were asking me how they would access the storage archive and how could they tell if they were actually moving files from the server not the cache. Were to look to see if they are opening up the mailbox.
If you know a link to a doc we can use as reference that would be a great help.
Let you know how we do.
You will see the online archive automatically in Outlook once it's enabled (see the screenshot in my original reply for what it looks like). The above link has more details on enabling it for users. Outlook syncs any changes made to the local cache back to the cloud can't make a change to local cache and not to the cloud mailbox, that's not how a cache works. You need policies in place to automatically move items to the online archive, but users can also drag and drop items from the primary mailbox to the online archive
Hi Dan,
I have managed to get the licenses and I am using my own account to experiment on. After playing around I got my OnLine Archive - mark@..... to show up. On my workstation client. So I only guessing but I open lets say SENT folder. Scroll to the bottom and click on "click here to view more on Microsoft Exchange" This allows me to get to the message on the server correct? Correct me if I am wrong. Here is what I tried to do. We started the subscription summer 2017. I can drag one at a time to move them. If I tagged ( Click first <shift> click last ) to move all sent in 2017. I get and hour glass and not responding, when I tried to move them to the Online archive folder in a bunch. Is there a limit of how many files you can move in a group? Small groups of email move slowly but do, large ones appear to stall and kick out.
Thanks for your help. Plowing forward in to the night.

Thanks Dan

Hi Dan,
Thanks again for all the help. Managed to get thing set up. See the on-line Archive in their accounts and started moving things. Slow process. Did I not read or see something where I can setup automatic maintenance that will move the mail into the on-line Archive for the users? I have looked around in Admin but don't see where I can manage this so I wondered if there was a way.
Thanks, Have a great weekend.
Hi Dan,
Thanks again. Just to let you know. After much digging and learning Microsoft's different terms for same old action and processes I was able to get the archive moving files. Thanks.