How to Fix Out of Memory or System Resources Error in Outlook?

Rollins Duke   
Published: May 10th, 2024 • 5 Min Read

Did you receive an error message i.e., Outlook out of memory or system resources? Many users unfortunately face stress when they see this error in Microsoft Outlook email client. But here the good news is that, in this write-up, we will discuss about out of memory or system resources error in outlook.

If you are looking for a solution to fix out of memory or system resources error in Outlook 2019, 2016, 2013, 2010, 2007, then feel relaxed. Here you will get complete information for resolving this Outlook error.

outlook out of memory or system resources error

Outlook Out of Memory or System Resources Error – Reasons

There are multiple reasons because of them, Outlook users see this error pop-up message. Let’s understand them now.!

If users try to connect multiple PST (Personal Storage Table) files with Microsoft Outlook. Then you may receive this error message. Now let’s understand this error message technically. When users access PST files in their Outlook accounts then it also creates cached data. But Outlook allots a specific limit for each added account / PST file. When Outlook reached its maximum limit. It shows a pop-up message like out of memory or system resource error in Outlook.

If users import a damaged PST file in Outlook, then it may be a cause of Outlook out of memory error. Sometimes corrupted PST files take more space than the actual size because of memory issues.

Outlook 2019 Out of Memory or System Resources Windows 10 / 11 – Methods

As we have mentioned above, we will explain the 4 different techniques for solving out of memory or system resources errors in Outlook error. Therefore, don’t waste your time and know all available methods.

#1 Reduce Unnecessary PST Files

If multiple PST files are connected with your Microsoft Outlook email client. Then you need to close some unnecessary PST files to avoid outlook out of memory or system resources error.

First Way –

  1. Run the MS Outlook email client on your computer and choose the Mail option from the navigation bar.
  2. Now you will see all imported PST files in Microsoft Outlook.
  3. Right-click on any PST file and click on the Close Outlook Data File Option.
    close outlook data file

Second Way –

  1. Start Microsoft Outlook on your machine and choose the Files option.
  2. After that, in the Account Settings option, choose Data Files.
  3. Thereafter, choose a PST file / account and click on Remove.
    remove account
  4. Using above mentioned methods, anyone can reduce PST files connected with Outlook.

#2 Use ScanPST.exe (Outlook Inbox Repair Tool)

If you are receiving Outlook out of memory or system resources error because of corrupted files. Then use this freeware ScanPST.exe utility to fix the error professionally. First, you need to find the ScanPST.exe setup file from Outlook directory. Thereafter, double click on this EXE file.

  1. Launch ScanPST.exe utility and select PST files that you want to fix by clicking on the Browse button.
  2. After uploading the corrupted PST file in the software interface, you need to press the Start button to continue.
    scan pst
  3. The PST file scanning process is running, so please wait for a while.
    pst file scanning
  4. The scanning process is completed successfully, now you can see the total number of errors found in the PST file.
    completed successfully
  5. Thereafter, you can click on the Repair button to correct the Outlook PST errors. Your file will be fixed within a few minutes.
    repair completed

At last, you can try to import this repaired PST file into Outlook to resolve the error.

#3 Reduce Cache Size by Registry

If you are not in a situation to remove the PST file from Outlook. Then it is advisable to reduce the cache size of PST files using the registry option.

  1. Shut down your MS Outlook email client if it is open on your pc.
  2. Press Windows + R to start Run program. After that type “Regedit” in search box and click on Ok.
  3. You can also directly search and open Registry Editor App.
    registry editor
  4. After that, you need to browse the following file explorer of Registry Editor App “HKEY_CURRENT_USER >> Software >> Microsoft >> Office >> <version> >> Outlook >> PST.
  5. Now right click on PST folder and choose New >> DWORD Value option.
  6. UseLegacyCacheSize” is the name of the newly formed value.
    out of memory or system resources error in outlook
  7. After that, set its value data as “1”.

#4 Smart Solution to Fix Out of Memory or System Resources Error in Outlook 2016 / 2019

Download PST Repair Tool by BitRecover to fix Outlook out of memory or system resources error. This software is also helpful for resolving different types of Outlook errors. This software has multiple advanced features that make it a special tool for resolving Outlook errors.

Download for Windows

  • Users can split large PST file into multiple smaller parts to overcome the oversize PST problems.
  • It permits to merge multiple PST files into one including emails, contacts, calendars, and other data.
  • The software allows to make healthy Unicode PST files from damaged files to fix the Outlook errors.
  • The tool has the capability to extract crucial data from PST files separately and store in multiple standard file extensions accordingly.


We have explained the top 4 methods to fix Outlook out of memory or system resources errors. You can try to resolve the Outlook error using any specific technique. You can also take expert advice to correct out of memory or system resources errors in outlook. BitRecover experts are available 24 hours to assist you.