“Troubleshooting: ‘OLM.DLL Not Found’ Error and How to Reinstall the Application”

If you encounter this error (‘OLM.DLL Not Found’), it means Outlook 2011 for Mac is inaccessible and needs to be reinstalled. However, the issue with reinstalling is that it could lead to the loss of previous data. Additionally, Outlook for Mac does not allow OLM files to be opened on other email clients or operating systems, limiting your ability to back up the data on other systems. To escape misplacing an important email database, it’s recommended to rebuild Outlook 2011 for Mac. This process not only fixes the “application failed to start” error but also helps recover your valuable data.
Multiple Types of ‘Missing OLM.dll’ Error Messages
Error messages associated to a corrupted OLM.dll file can appear in different forms, as shown in the image below:

Before diving into the solution, let’s review the common symptoms that occur when Outlook for Mac stops responding as expected:
Common Symptoms of Outlook 2011 for Mac Issues:
- Slow and Unresponsive Mac: Your system may become sluggish and unresponsive when trying to use Outlook.
- Applications Freeze or Crash: Outlook and other applications may freeze or crash frequently without warning.
- “Access Denied” Message: You may see an “Access Denied” message, preventing you from accessing your emails.
- File Not Found: Users may be unable to locate their data files, leading to confusion and potential data loss.
- Error Messages: Outlook displays error messages with descriptions and potential resolutions, often without resolving the core issue.
- System Shutdown: The Mac system may terminate unexpectedly after a certain period of time.
Factors That Trigger These Symptoms:
Several factors can lead to corruption of the Outlook 2011 data file and cause the issues mentioned above. Common reasons include:
- Sudden Network Failure or Unexpected Server Problems: Interruptions in the network or server can result in corrupted data files.
- Malware Attacks: A malware infection on the network can damage Outlook’s data files.
- Exchange Server Crash: A crash in the Exchange server can lead to data corruption.
- Improper Installation of Outlook for Mac: If Outlook is not installed properly or if there’s an interruption during installation, it can cause issues.
- Corruption in Storage Media: Problems with the storage device where Outlook is installed can lead to data file corruption.
- Unexpected App Crashes: Outlook may crash due to unexpected issues, leading to potential data loss.
- Corruption throughout Update Procedure: If Outlook for Mac encounters corruption during an update, it may result in the application failing to function correctly.
There could be several reasons that lead to data corruption in Mac Outlook. Regardless of the cause, repairing and rebuilding Outlook for Mac is crucial for efficient data recovery. Below are the steps to rebuild your Identity Database:
Steps to Rebuild Your Identity Database
#1: Close All Applications
- Press on the application name in the top menu bar and select the Quit option.
- Hold down the Command and Option keys, then press the Escape key on your keyboard.
- In the Force Quit Applications window, select the application you want to quit and click the Force Quit button. (Note: You cannot quit the Finder window.)
- Close any open windows by clicking the red circular icon in the top left corner of each window.
#2: Check Available Space on Your Hard Disk
Before starting the maintenance procedure, ensure you’ve sufficient space on your hard drive. Typically, database maintenance requires double the amount of space as your current Outlook database size. In this case, you should have three times the space available. For instance, if your Outlook database is 1 GB, you will need 3 GB of free space to ensure efficient rebuilding.
#3: Back Up Your Current Identity
Backing up your current identity is crucial to prevent data loss during the process.
- Open Finder and hit on Go > Home.
- Navigate to the Documents folder.
- Open the Microsoft User Data folder.
- Right-click on the Office 2011 Identities folder and select Duplicate to create a copy.
- Quit all applications.
By following these steps, you’ve successfully generated a backup of your current identity.
Step 4: Rebuild the Database Using the Inbuilt Utility
Now, you can proceed with rebuilding the database using Outlook’s built-in utility.
- Close all applications.
- Hold down the Option key and launch Outlook 2011 or navigate to the Applications Folder and open the Microsoft Office 2011 folder.
- Double-click the Microsoft Database Utility app.
- Choose your database and press on Rebuild to start the repair process.
#5: Verify If the Problem is Resolved
Start the Outlook 2011 application and check if the issue has been fixed. If the problem is resolved, you can continue using Outlook 2011 for Mac. However, if the issue persists, it’s time to create a new identity to further resolve the error.
This step is particularly relevant if you have multiple identities configured on the same system. Outlook allows you to have different identities, each with its own set of emails, address books, tasks, calendars, and account settings. Corruption in a single file may affect multiple identities. In such cases, creating a new identity may help resolve the issue.
Step 6: Make a New Identity in Outlook 2011
- Quit all applications.
- Hold down the Option key and launch Outlook to open the Microsoft Database Utility.
- Click the (+) sign to add a new identity.
- Enter a name for the new identity.
- Set the newly created identity as the default identity.
- Quit and restart Outlook.
After creating a new identity, check if the issue has been resolved.
If the database remains corrupt despite rebuilding the identity, it is likely the corruption is beyond manual repairs. At this point, consider using specialized software to resolve the issue. One such tool is CubexSoft Mac OLM Converter, which not only repairs the corrupt data but also convert OLM files into various formats, if necessary. You can choose to repair specific folders or the entire database, depending on your needs.
Final Lines
Outlook 2011 for Mac is a main app for managing emails and data. If the database becomes corrupted, it can significantly impact your Mac’s performance. Rebuilding the database can sometimes resolve the issue, but if the problem persists, using OLM Converter for Mac & Win OS is the best solution. This tool offers an intuitive graphical interface and is compatible with all Outlook editions, making it easy for both professional and novice users to convert their OLM to PST, PDF, EML, MSG, MBOX, vCard, Yahoo, Gmail, IMAP, Thunderbird, Amazon WorkMail, Zimbra, Windows Live Mail, Office 365, and more.
