If you cannot open your Outlook data file or suspect that the file is damaged, use the Inbox Repair tool (scanpst.exe) to repair errors in the file.

If some Windows functions aren't working or Windows crashes, use the System File Checker to scan Windows and restore your files. Though the steps below might look complicated at first glance, just follow them in order, step-by-step, and we’ll try to get you back on track.

Press the Windows logo key + R. Type msconfig in the Open box and then select OK. Select the Boot tab. Under Boot options, clear the Safe boot checkbox. Find out how to boot into safe mode in Windows from Settings, the sign-in screen, and a black or blank screen.

Install Microsoft 365 2019 or 2016 on a PC. Remember a one-time purchase version of Microsoft 365 is licensed for one install only. Depending on your browser, select Open file (in Edge or Internet Explorer), Setup (in Chrome), or Save File (in Firefox).

Use the Office offline installer to install Office 2016 or Office 2013 if you don't have an active Internet connection or you're having problems with slow speed or unreliable connections.

If installation doesn't start automatically, browse the disc to find the program setup file, usually called Setup.exe or Install.exe. Open the file to start installation. Insert the disc into your PC, and then follow the instructions on your screen.

If you already redeemed a product key, you're simply reinstalling the apps, or you know you have an assigned license through work or school, you can skip ahead and go to the section sign in to download and install Microsoft 365 or Office.

Select File > Get Add-ins. Alternatively, you can also view your add-ins directly from the Home tab by selecting Add-ins . You can directly install add-ins from this page or select More Add-ins to explore. In the Office Add-ins dialog, select My Add-ins tab.

When you select the Import Settings option during setup, the web add-in counterparts of your existing COM add-ins in classic Outlook for Windows are installed in the new client. The following table lists the applicable COM add-ins and their web add-in counterparts.

1. Right-click the Start button, and click Run. 2. Type Outlook.exe /safe, and click OK. Tip: If Windows can't find Outlook.exe /safe, try using the full path to Outlook (for example C:\Program Files\Microsoft Office\OfficeXX, where XX is your version number).