How to Start Outlook in Safe Mode and Create a New Profile

If classic Outlook crashes when it opens, freezes, runs very slowly or refuses to sync, two tools solve a large share of problems: Safe Mode, which starts Outlook without add-ins, and a new profile, which rebuilds Outlook’s account configuration from scratch. This guide applies to classic Outlook for Windows (included with Microsoft 365 and Office).

If your main symptom is that new email simply isn't arriving, start with our broader guide to Outlook not receiving or syncing email – Safe Mode and a new profile are two of the steps in that process.

Part 1: Start Outlook in Safe Mode

Safe Mode starts Outlook with all add-ins disabled and without some customisations. If Outlook works normally in Safe Mode, you know an add-in is the cause.

Method 1: Hold Ctrl

1. Close Outlook completely.
2. Hold down Ctrl and click the Outlook icon.
3. When asked “Do you want to start Outlook in safe mode?”, select Yes.

Method 2: Use the Run box

1. Press Win+R.
2. Type the following and press Enter:

outlook.exe /safe

3. If asked to choose a profile, select your usual profile and click OK.

The title bar shows (Safe Mode) while it’s active.

Part 2: Find and disable the faulty add-in

If Outlook behaves normally in Safe Mode:

1. Close Outlook and open it normally (if it crashes immediately, stay in Safe Mode for this step).
2. Go to File › Options › Add-ins.
3. At the bottom, next to Manage, choose COM Add-ins and click Go.
4. Untick all add-ins, click OK and restart Outlook normally.
5. If Outlook now works, re-enable add-ins one at a time, restarting Outlook each time, until the problem returns. The last add-in you enabled is the culprit.

Then update, reconfigure or remove the problem add-in. Common culprits include old PDF tools, CRM connectors and meeting plug-ins. In organisations, some add-ins are deployed centrally – speak to IT before removing them.

Part 3: Create a new Outlook profile

If Safe Mode doesn’t help, the Outlook profile may be damaged. A profile stores your account settings and links to local data files. Creating a new one is safe and often fixes sync failures, repeated password prompts and startup errors.

POP accounts: if your email uses POP rather than Microsoft 365, Exchange, Outlook.com or IMAP, your messages may only exist in a local .pst file. Find its location first (in classic Outlook: File › Account Settings › Account Settings › Data Files) and keep a copy.

Step 1: Open Mail settings

1. Close Outlook.
2. Open Control Panel (search for it in the Start menu).
3. Set View by to Large icons and select Mail (Microsoft Outlook). (On some systems it’s labelled Mail (Microsoft Outlook 2016) or similar.)
4. Click Show Profiles.

You can also open Outlook, go to File › Account Settings › Manage Profiles.

Step 2: Add a new profile

1. Click Add, enter a name such as Outlook-New, and click OK.
2. Enter your email address. For Microsoft 365 and Outlook.com accounts, Outlook usually configures everything automatically after you sign in.
3. Complete the setup and click Finish.

Step 3: Make it the default and test

1. Back in the Mail window, select Always use this profile and choose the new profile from the list.
2. Click OK and open Outlook.

Outlook will download your mailbox, which can take a while for large mailboxes – leave it open and connected. If everything works, you can return to Show Profiles later and remove the old profile.

If you rely on any custom items stored only on the old profile, such as a POP .pst file or archive files, reconnect them via File › Open & Export › Open Outlook Data File.

What about new Outlook?

New Outlook for Windows doesn’t use COM add-ins or profiles in the same way. If it misbehaves:

• sign out of the account in Settings › Accounts and sign back in;
• go to Windows Settings › Apps › Installed apps, find Outlook (new), select Advanced options if available, and choose Repair or Reset;
• check whether the problem also happens in Outlook on the web – if it does, the issue is with the account or service, not the app.

Conclusion

Safe Mode tells you quickly whether an add-in is breaking Outlook; disabling add-ins one by one identifies the culprit. When the problem lies deeper, a fresh profile rebuilds Outlook’s configuration without touching server-based email. Together they fix most classic-Outlook crashes and sync issues without reinstalling Office.