Outlook - Repair, Rebuild, or Create an Outlook Profile

Overview

An Outlook profile stores the account connections, data files, and Outlook settings that control how your mailbox works on the computer. Creating a new profile, repairing an account, or rebuilding the local cache can resolve many Outlook issues without affecting mailbox data stored online.

Use this process if Outlook is slow, freezes, cannot send or receive mail, shows missing or outdated mailbox items, repeatedly shows Disconnected, Trying to connect, or Need password, has shared mailbox sync issues, shows temporary mailbox prompts, or returns incomplete search or calendar updates.

Instructions

Recommended troubleshooting order

Start with the least disruptive option below and only move to the next step if the issue remains. In most cases the best order is: repair the account in Outlook, reset the OST cache, create a new profile, and finally repair Microsoft 365/Office if Outlook itself appears damaged.

Option 1: Repair the account in Outlook

1. Open classic Outlook.

2. Select File.

3. Select Account Settings > Account Settings.

4. On the Email tab, select the affected account and choose Repair.

5. Follow the prompts, then restart Outlook when finished.

Option 2: Reset the OST cache

Use this option when Outlook opens but mailbox content is stale, shared mailboxes are not updating, folders show old items, Outlook repeatedly reconnects, or the profile seems desynchronized from Microsoft 365.

1. Close Outlook completely.

2. Open File Explorer.

3. In the address bar, enter %LOCALAPPDATA%\Microsoft\Outlook and press Enter.

4. Find the OST file for the affected mailbox.

   Open

   

5. Rename the file by adding .old or .bak to the end.

6. Reopen Outlook. Outlook will create a new OST file and resync the mailbox.

Option 3: Create a new Outlook profile

This is the preferred rebuild method when the current profile appears corrupted, Outlook is unstable, or sync issues continue after an account repair. Microsoft’s current guidance is to use the profile picker.

Recommended method

1. Open the profile picker using one of these methods:

   • Hold the Shift key while starting Outlook. Once the window opens you can stop holding Shift.

   • Press Windows + R, type Outlook.exe /profiles, then press Enter.

     Open

     

   • In Outlook, select File > Account Settings > Change Profile. Outlook will close, then reopen to the profile picker.

2. In the profile picker, select Options, then select New.

   Open

   

3. Enter a name for the new profile and select OK.

4. Add your email account and complete the sign-in prompts.

5. After setup, either:

   • enable Prompt for a profile to be used

   • set the new profile as the default profile.

6. Open Outlook and allow it to finish syncing. It will take some time.

If the new profile works correctly, go back later and remove the old profile. Do not copy a profile that you believe is corrupted, because that can carry the problem into the new profile.

Option 4: Repair Microsoft 365 / Office

The old “Repair Profile From Control Panel” article is not actually a profile repair. It repairs the Microsoft 365 / Office installation. Use this when Outlook itself is crashing, Office components appear damaged, or profile rebuild steps do not fix the problem.

1. Close all Office apps.

2. Open computer Settings > Apps > Installed apps.

3. Select Microsoft 365 Apps or Office and choose Modify.

4. Run Quick Repair first if you want the faster offline option.

5. If the issue remains, run Online Repair, which is more thorough and can reinstall components.

6. Restart the computer and test Outlook again.