Due to the large number of affected users, the automated fix took time https://fixoutlookhelp.wordpress.com/2025/10/29/repair-outlook-ost-and-pst-files-2025-guide/ to apply. Microsoft advised using a manual workaround to restore access more quickly. A notification will be sent once the incident is fully resolved. We can diagnose and fix several common Outlook connectivity issues for you. If our automated tool can't fix your issue, or you'd like to fix it yourself, see the next section. Sometimes, antivirus real-time scanning can slow Outlook down.
Then, right-click a selected file and choose "Delete" (a trash can icon). You might need to set Windows Update to automatically download and install recommended updates. Installing any important, recommended, and optional updates can https://fixoutlookhelp.wordpress.com/2025/10/29/repair-outlook-ost-and-pst-files-2025-guide/ often correct problems by replacing out-of-date files and fixing vulnerabilities. To install the latest Windows and Office updates, click the link below. In Windows, Outlook not opening errors can disrupt email communication, which can negatively affect productivity and business operations.
Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. Corrupted Outlook files are a common cause related to Outlook. To rectify/repair it, Microsoft has provided an inbuilt utility called Scanpst.exe. As a result, you can choose any of the troubleshooting solutions accordingly.
In some scenarios, doing so fixes the "Outlook will not open" issue. However, if installing updates doesn’t fix the problem, then try to repair your Office programs. Then, you can try to start Outlook 2016 in Safe Mode and then check which add-in is causing Outlook not Opening On Windows 10, https://fixoutlookhelp.wordpress.com/2025/10/29/repair-outlook-ost-and-pst-files-2025-guide/, issues, disabling that add-in.
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.
One of the failed sign-in windows showed a long string under a field labeled Microsoft Information Protection API. Running that value through the Entra admin portal revealed what we needed. At that point, the focus shifted to what was happening during authentication. The answer came from a closer look at the Microsoft Entra sign-in logs and a hidden dependency that I wasn’t aware of.
Repeat the process for all the add-ins that were selected earlier and wait until the Outlook crashing problem repeats. 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). The steps to access the repair tool vary depending on your operating system.
The funny thing is that https://fixoutlookhelp.wordpress.com/2025/10/29/repair-outlook-ost-and-pst-files-2025-guide/ the new "modern" Outlook worked fine, though, which made things even more confusing. We looked at the sign-in logs, tested new accounts, and eventually found what was really going on. Microsoft Outlook is one of the most widely used email clients globally, especially in professional and business environments. Outlook also comes with strong built-in security features, making it a reliable choice for managing communication and workflow.
Installing any important, recommended, and optional updates can often correct problems by replacing out-of-date files and fixing vulnerabilities. To install the latest Windows and Office updates, click the link below. I'm having an issue with one Outlook 365, the program open and get stuck at loading the https://fixoutlookhelp.wordpress.com/2025/10/29/repair-outlook-ost-and-pst-files-2025-guide/ user profile, any profiles. If you typically use an Outlook.com account for email, this issue can occur if there are multiple aliases on the account and the 3rd party email address is the primary alias. We have recently received some reports of users who are experiencing issues with subscribing to .ics/ical calendars.
You cannot create a new email address with @live.com as the domain address. You cannot create a new email with @msn.com as the domain address. If you have not logged in to your email address in over two years, it will be considered inactive and may have been removed. The first rule of Outlook troubleshooting is to eliminate the most obvious suspects. A popular one to cross off is your own internet connection. We go above and beyond the average software reseller because we built our business on trust.
Here, we list fixes for the possible causes, starting with the most likely culprit. Go in order so you have best chance of getting back to your inbox as quickly as possible. Occasionally, classic Outlook tries to run a process in the background. Auto-archive, sending and receiving a very large attachment, or running some of the other mailbox tools can all be done in the background. Check the status bar at the bottom of the screen to see if another process is running. If so, wait a short time (usually two or three minutes) to see if Outlook starts working again.