How to resolve 'Not Responding' errors and hang-ups in Microsoft Outlook

Summary

This guide helps you troubleshoot and resolve: How to resolve 'Not Responding' errors and hang-ups in Microsoft Outlook. Follow the steps below to fix the issue.

Common Causes

Microsoft Outlook is a critical tool for business communication, but it can occasionally become unresponsive or "hang," leaving you unable to send emails or access your calendar. This is often caused by corrupted data files, conflicting third-party add-ins, or a bloated local cache. If you find that other applications are freezing or crashing as well, you may have a broader system issue with your system resources.

Quick Fix Steps

Before diving into deeper technical repairs, try these rapid solutions to resolve temporary glitches:

• Restart Outlook: Completely close the application and relaunch it.
• Check your connection: Ensure your internet is stable. If you notice your browser is not loading pages, the issue is likely network-related rather than an Outlook fault.
• Force Quit: If Outlook is completely frozen, press Ctrl + Shift + Esc to open Task Manager, select Microsoft Outlook, and click End Task.

Detailed Instructions

Step 1: Start Outlook in Safe Mode

Safe Mode launches Outlook without any add-ins. This helps determine if a third-party plugin is causing the "Not Responding" error.

1. Press Windows Key + R on your keyboard to open the Run dialogue.
2. Type outlook.exe /safe and press Enter.
3. If Outlook runs smoothly in Safe Mode, an add-in is likely the culprit.

Step 2: Disable Faulty Add-ins

If Safe Mode resolved the issue, follow these steps to identify and disable the problematic add-in:

1. In Outlook, go to the File tab.
2. Select Options > Add-ins.
3. At the bottom of the window, ensure Manage: COM Add-ins is selected and click Go....
4. Uncheck all active add-ins and click OK.
5. Restart Outlook normally. If it works, re-enable the add-ins one by one to find the one causing the crash.

Step 3: Repair the Outlook Data File (.pst or .ost)

Corruption in your local data file can lead to frequent hangs, especially when searching or opening large folders.

1. Close Outlook completely.
2. Navigate to the Office installation folder on your drive (typically C:\Program Files\Microsoft Office\root\Office16).
3. Find and run the SCANPST.EXE tool.
4. Click Browse to select your Outlook data file.
5. Click Start to analyse the file. If errors are found, click Repair.

Step 4: Clear the Outlook Cache

A bloated cache can slow down performance and cause the application to stop responding during synchronisation.

1. Close Outlook.
2. Press Windows Key + R.
3. Type %localappdata%\Microsoft\Outlook and press Enter.
4. Locate the folder named RoamCache.
5. Select all files within this folder and delete them. (These are temporary files and will be recreated automatically).

Step 5: Create a New Outlook Profile

If the issue persists after the steps above, your Outlook profile may be corrupted. Creating a new profile can resolve persistent hangs:

1. Close Outlook.
2. Open the Control Panel and search for Mail (Microsoft Outlook).
3. Click Show Profiles > Add.
4. Enter a name for the new profile and follow the prompts to add your email account.
5. In the General tab, set Always use this profile to your new profile and click OK.
6. Restart Outlook and test whether the issue is resolved.

Further Troubleshooting

Check for System Resource Exhaustion

If Outlook continues to hang, your computer may be running out of available memory (RAM). You can check this in the Performance tab of the Task Manager. If CPU or Memory usage is consistently above 90%, please refer to our guide on Computer running slow.

Critical System Failures

In rare cases, Outlook crashes may be a symptom of a deeper OS failure. If your computer restarts unexpectedly or you encounter a Blue Screen of Death (BSOD), please stop troubleshooting and Open a Ticket immediately for a technician to analyse your system logs.

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