Do you fail to send or receive any email through your Outlook?

Each time you try, Outlook prompts the message store has reached its maximum size.

The good news is, you have come to the right place indeed. In the entire article, I will disclose all possible fixes. After applying them, you will be able to send or receive emails through Outlook. Let’s explore the fixes.

Troubleshooting – ‘The Message Store Has Reached Its Maximum Size’

The error becomes evident, which means, Outlook crosses the 50 GB storage limit. Here you have a couple of options in hand to fix the error. Before diving into the in details fixes, let’s have a glimpse of the list.

• Fix 1: Customize Registry Editor settings
• Fix 2: Archive data
• Fix 3: Compact OST/PST file
• Fix 4: Export/import oversize PST file
• Alternative fixes

Fix 1: Customize Registry Editor Settings

Close your Outlook and try to customize Registry Editor first. You can do it by following the described steps one by one.

Step 1

In the beginning, you need to press the Windows and ‘R’ keys together. Consequently, ‘Run’ will appear. Then, you have to type ‘regedit’ on the ‘Open’ box and click on ‘Ok’.

Step 2

In this step, you need to copy the following direction and paste it on the Registry Editor search box-

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\PST

For your kind info, the direction will be valid for Outlook 2016, 2019 & 365.

By any chance, if the key ‘PST’ doesn’t exist, right-click on the ‘Outlook’ key. Here you have to expand ‘New’,. So the ‘Key’ option will be visible. Then click on it.

After that, a new key will be creat and you have to rename it as ‘PST’

Step 3

You will see the ‘MaxLargerFileSize’ and ‘WarnLargeFileSize’ at the right sidebar. Here you have to work with the option.

Step 4

Next, double click on the ‘MaxLargerFileSize’. As a result, an interface of ‘Edit DWORD (32- bit) value’ will appear on the screen. You need to change the value and select ‘Decimal’ as the parameter.

In general, Outlook has a maximum of 50GB limit access. In this case, you can put 51,200 in the Value data box.

Step 5

Then, double click on the ‘WarnLargeFileSize’. Consequently, the ‘Edit DWORD (32- bit) value’ interface will appear. Again, you need to change the value data and select ‘Decimal’ as the parameter.

Here, you have to put 48640 (95% of 51200) as a warning value data.

Additional Step

If the ‘MaxLargerFileSize’ and ‘WarnLargeFileSize’ would not exist, you have to right-click on the blank space of the right sidebar. Then, you would expand ‘New’ and select the ‘DWORD (32- bit) value’ option.

In the end, rename the file as ‘MaxLargerFileSize’. You have to do the same again to create the ‘WarnLargeFileSize’ value. 

Finally, try to use Outlook. If the problem still exists, I would tell you that the way is not ending here. 

Fix 2: Archive Data

From this step, you have to work with Outlook directly to reduce the storage. Here, you can try to archive data first. I will describe the process step by step.

Step 1

Firstly, open MS Outlook. Then, you have to tap the ‘File’ tab.

Step 2

Here you will see the ‘Info’ option on the top left corner. In the ‘Info’ section, you will find the ‘Tools’ option.

Step 3

While clicking on it, the option ‘Clean Up Old Items’ will become evident. You have to select it.

Step 4

Then you will see the ‘Archive this folder and all subfolders’ and mark on it. At the bottom of the ‘Archive’ box, you have to mark on the box- ‘Include items with “DO not AutoArchive” checked. 

You also have to select a date that would indicate the desired archived items mentioning the date.

Finally, click on the ‘Ok’ and check the issue that will be solved or not?

Fix 3: Compact OST/PST File

In this stage, I reveal a short process to decrease the storage data. You can do it by following some easy steps.

Step 1

Open the Outlook again. Go to ‘File’ and select the ‘Info’. As a result, ‘Account Settings’ will appear on the right sidebar. You will find another same-named option inside it.

Step 2

While selecting the ‘Account Settings’, a new interface will be visible. Here you have to tap the ‘Data Files’ tab.

Step 3

Then tap the ‘Settings’ option. You will find it under the ‘Data Files’.

Step 4

After that, the ‘Outlook Data File’ interface will become evident. Here you will find the ‘Compact Now’. Finally, you have to click on ‘Ok’.

Let’s have a check Outlook again. Do you get access to sending email or not?

Fix 4: Export/Import Oversize PST File

Export/import oversize PST (personal storage table) files might be another best option to fix the issue. You will apply it easily.  

Step 1

To export/import the oversized PST file, you need to work with the ‘Data Files’ option again. To do that, you have to follow the previously described steps. You have to click on the ‘Add’ tab whenever the ‘Data Files’ will appear.

Step 2

Next, you would type a name with ‘.pst’ for creating the PST file and press ‘Ok’. A new PST file will appear in the ‘Data Files’ box.

Step 3

From this step, the second phase of the running fix will start. Here you need to tap the ‘File’ on Outlook and select ‘Open & Export’. Then you will see the ‘Import/Export’ option.

Step 4

While entering into the option, a new interface- ‘Import and Export Wizard’ will become evident. You have to select the ‘Export to a file’ from here. Then, press ‘Next’.

Step 5

Here, you will see the previously created .pst file. You have to select it and click on ‘Next’.

Step 6

In this step, you need to mark on the ‘Include subfolders’ from the ‘Export Outlook Data File’ box and tap on ‘Next’.

Step 7

Consequently, the ‘Browse’ section will be visible. You have to browse the file. Also, you have to mark the ‘Do not export duplicate items’ option. And finally, press the ‘Finish’ tab.

Alternative Fixes

Here I will add some alternative fixes. You can follow it also. The fixes will help you to reduce your Outlook storage data.

• Unsubscribe: You concise the Outlook storage easily by unsubscribing the email that has less important.
• Delete: You also may delete the existing mails that have no need anymore. That can be Conversation History, Draft, Junk E-Mail, Reminders, Restored Items, Sent items, etc.
• Remove attachment: Removing the attachment without deleting the email can be possible. You have to right-click on the attachment. Then the ‘Remove Attachment’ option will appear. Just click on it. Consequently, the process will be complete. Now, you can save your Outlook storage.
• Mailbox Cleanup: The use of Mailbox Cleanup is another good option to reduce the Outbox storage size. There are multiple options like ‘View Mailbox Size’, ‘Find’ for search mail by size measurement, ‘AutoArchive’, ‘Empty’ for deleting files permanently, and ‘Delete’ for reducing alternate versions of mail. You have to edit the options.

Final Words

By any chance, if you feel that the technical fixes (fix1 to fix4) are complex, I would recommend you to try the alternate fixes. But believe me, all the fixes are easy to apply DIY. You just have to follow the step-by-step procedure.