Compatibility mode is suitable for older software with Windows 10 that fail to run normally. Thankfully, Microsoft Outlook is fully optimized for Windows 10, meaning Compatibility mode is not necessary. You might be wondering what happens when you switch on the Compatibility mode for Outlook. When you do this, your Outlook might have opening problems. For this reason, you should always turn off Compatibility mode for Outlook.

• You might be wondering what happens when you switch on the Compatibility mode for Outlook.
• This goes to prove that the problem came from your original Outlook profile.
• When Outlook does open, it will send mail fine one minute and then the next minute it will not send any mail.
• It seems like something went wrong on Microsoft update and they might recall it or fix it, so we might need to wait untill that.
• If you restart it successfully, it will show you that one or more add-ins are defective.
• Follow the steps below to download the uninstall support tool according to your browser.
• When you do this, your Outlook might have opening problems.
• It is a powerful and almighty software that can be applied to fix corrupt Outlook PST files in any scenarios.

Older versions of Outlook may be out of support

Now, it's time to uncover them by the elimination process. Follow the steps below Office 365 Sync Errors Fix to download the uninstall support tool according to your browser. Uninstall the Microsoft application restart the device and re install the Microsoft application and restart the device.

Why Won't Outlook Open?

Should you decide to remove a profile, back up the data files first. All offline cached content will be deleted when you choose Remove. For more information, see Introduction to Outlook Data Files (.pst and .ost). If you are trapped in a similar situation that my Outlook is not opening, you may feel disturbed about the problem. If Outlook is NOT able to start in safe mode, then try the next proposed solution below, entitled Create a new Outlook profile.

My Outlook won't open. It's an on-going problem. This time, though, when I shut down my laptop, and rebooted it, I am

You can run the Inbox Repair Tool (scanpst.exe) to scan your Outlook data files and repair errors. Are you having trouble starting Outlook or receiving "Cannot start Microsoft Outlook. Cannot open solve Office 365 mailbox sync delays the Outlook window" error messages? We can fix the problem for you, or you can use the troubleshooting steps we're providing below to help resolve these startup issues. Here's the deal, when Outlook manages to open, all the files you delete will automatically be recreated. It gets better because you also resolve all the Outlook opening issues. Please follow the steps specified in the below link.

Getting Started Is Easy

Knowing the cause of the problem will help you sort out all the issues related to Outlook opening. Outlook stores all your email messages, meetings and events, contacts, and tasks in data files. These files occasionally might become corrupted.

Repair corrupt Outlook data files

If you would like for me to fix this issue using our Secure Remote Assistance then customer care can setup a new case for us. Occasionally, that profile can become corrupted. You can determine if it's corrupted by creating a new profile and changing which profile is used when Outlook starts. Use the classic Outlook startup troubleshooter to diagnose and fix several common classic Outlook for Windows issues for you. If you restart it successfully, it will show you that one or more add-ins are defective.



Microsoft Outlook provides a better experience for users. With great functionality, you can manage your email, contacts, calendar as you like. Check the solutions to fix "Outlook not opening" problem and Recreate Outlook Profile Step By Step how to avoid "Outlook won't open" again. Thanks for bringing this to my attention and I can see the urgency of this matter. Open the application and sign in to your Microsoft application to activate.