If you have a large number of items in any single folder, you may experience performance issues during certain operations. For more information, see Outlook performance issues when there are too many items or folders in a cached mode .ost or .pst file. An out-of-date antivirus program may sometimes cause errors when you try to start Outlook as there may be compatibility issues between your antivirus program and Outlook.

The good news is that most "Outlook won’t open" errors can be resolved with a few proven troubleshooting steps. When you install Office, an Inbox Repair Tool (SCANSPST.EXE) is also installed on your PC. The Inbox Repair Tool can resolve issues by scanning your Outlook data files and repairing errors.

Sometimes, when Outlook isn’t working right, a simple restart can help. When you turn your computer off and on again, Outlook and your computer may solve many problems. As a result, it helps to clear out any issues or things that might be causing trouble, like when you clean up a messy room.

After reinstalling, now it freezes constantly, even when not in use. Roughly every 5 seconds, the window freezes, grays out, and gives a "not responding" message--just as before. But it happens constantly without me even doing anything in Outlook now. Outlook works best when it's up steps to fix Outlook not opening to date. We recommend setting Windows Update to automatically download and install recommended updates.

We can fix the problem for you, or you can use the troubleshooting steps we're providing below to help resolve these startup issues. A corrupted profile, a damaged PST file, faulty add-ins, or improper Outlook startup settings often cause this issue. 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 Outlook worked correctly the last time and nothing has changed about your account configuration, then checking if things work correctly in Safe Mode is a good first step.

If you have email messages in an email program, you must import your email messages and addresses to the new user profile before you delete the old profile. If everything is working correctly, you can now delete the old profile. To manage your mailbox by reducing the size of the Outlook data file, see Reduce the size of Outlook Data Files (.pst and .ost). The above procedures will help you to resolve the Microsoft Outlook Stuck on Loading Profile error.

The root cause was the deployment of an incorrect campaign data file, which led to false positive campaign detection. We have since reverted to the right data file and the outbound email flow has returned to a normal state. We also released a new rule that corrected the wrong campaign verdict for all impacted customers during the incident. If you're having problems sending or receiving email, read how to Fix Outlook.com email sync issues. Maybe you've added a new program to your computer that doesn't get along with Outlook, or your system has a virus.

Besides that, its free edition can process up to 50 items from each folder, making it easy for users to understand tool’s steps to fix Outlook not opening working. We have shared everything on the manual and professional ways to fix Outlook data files or Personal Storage Table (PST) in this blog. Also, we go over the stepwise working procedure of both solutions and the reasons behind PST file corruption issues. The Inbox Repair tool or ScanPST.exe is not a convenient way because of multiple restrictions. After you run the Inbox Repair tool, you can start Outlook and recover repaired items.

Whether you are a Microsoft Outlook, Exchange or steps to fix Outlook not opening Office 365 user, you may come across or encounter the PST files. These Outlook data (PST) files store user’s data, including email messages, calendars, tasks, journals, etc. However, if the SCANPST or Inbox Repair tool fails to repair the PST file, remember to use an advanced Outlook PST repair tool, such as Stellar Repair for Outlook. It can repair corrupt, inaccessible, or encrypted PST files of any size, with complete integrity. Remember that the backup file was the original corrupted file, and you may find that you cannot recover anything other than what was recovered in the Lost and Found folder. If you cannot import the Newname.pst file into Outlook, unfortunately you have lost all the information that is not in the Lost and Found folder.

Sometimes, when you’re using Outlook, it might ask for your confirmation before doing something. For example, if you try dismissing all reminders, Outlook might show a message asking, ‘Are you sure you steps to fix Outlook not opening want to do that? ’ You’ll need to choose an option for Outlook to continue. To troubleshoot the "Outlook Won’t Open in Windows 10" error, try these solutions.

Bug fixes, new features, and performance enhancements are released regularly. If you try to delete or move a large number of messages at once, Outlook can appear to freeze, but really, it's working behind the scenes. Check the status bar at the bottom of the screen. If Outlook is performing some operation on hundreds or thousands of messages at once, it might appear to be stuck. Give Outlook a few minutes to finish the process and it should start to work again. To determine whether this problem is caused by a corrupted user profile, create a user profile to see whether the problem still occurs when you use the new profile.