However, for severely corrupted PST files, it’s steps to fix Outlook not opening recommended to use a third-party repair tool. In this regard, we recommend Kernel for Outlook PST repair tool to save your precious time. Problems with the device, connection to power, network issues, viruses or malware, oversized files, and improper shutdowns all cause the PST file to act up. The issue might be difficult to identify if you have multiple accounts and a long history with Office 365, Exchange, and Outlook.

If you are using Outlook on a PC, you can check to see what is currently permitted by your computer or try to reset the Credential Manager and remove any old passwords. The Credential Manager is where Windows stores passwords and login information on your computer. It acts as a vault with specific settings and permissions you can adjust. It could be as simple as an out-of-date version of Outlook's software. Once an update has been run on your system, the bug may be rectified.

We will ensure that all information is retained and only contacts with matching information in all fields will be cleaned up. To check if you have received the fix, review your contact list to confirm steps to fix Outlook not opening duplicates have been removed. This issue has been mitigated and we are continuing to monitor the issue to ensure stability.

Often there is the option to add sites to a whitelist, and you can give more permissions to Outlook. The easiest way to find out if this is the problem is to temporarily disable your antivirus software and log in to Outlook as usual. If the prompts go away, you'll know it was the antivirus software. There are a number of reasons this issue arises, which makes it even more infuriating. It could be an issue with a setting on the account, or it could be something external that is blocking normal functions in Outlook.

These applications and services can interfere with Outlook. A Selective Startup or "clean boot" process can help you identify problems that are caused by application conflicts. Corrupted PST or OST data files can prevent Outlook from loading. Microsoft’s ScanPST tool can repair minor corruption