
So, before you begin this procedure, please ensure Outlook is not running on your computer.Conclusion. For example, when you edit, delete, send or receive an email in Microsoft Outlook, the changes will also be updated on the Microsoft Exchange Server.Setting up a connection to the Microsoft Exchange Server. That is as and when the Outlook sends and receives emails or any other folder is updated, simultaneously it even updates the Exchange Server about these changes. I clicked on 'View Certificate' and installed the certificate, but I still get this dialog each time I start Outlook.Synchronization is a built-in process in Microsoft Outlook that happens regularly whenever the PST files or OST file gets updated. The target principal name is incorrect. When I start Outlook, I get an 'Internet Security Warning' dialog box with the message The server you are connected to is using a security certificate that cannot be verified.

Connect to outlook mobile, I always get a message saying, mail server timed out.Check If Your OST File Is Synchronized Or NotRe-synchronize Outlook folders To Email Sync IssueEmpty The "Sync Issues \ Local failures" FolderFix your OST or PST file To Repair Outlook Email Sync IssueIn case you are facing Outlook sync issues due to a corrupt or damaged PST file and are looking to restore your precious Outlook data, we recommend you to repair your Outlook data file using Remo Repair Outlook. 5 Ways to Fix Outlook Sync IssuesFollow these steps in Outlook 2010 and later to check and turn on the. However, before trying to fix, convert the OST file to PST using OST to PST converter tool and backup the Outlook data. So, follow the steps given in the below section and know how you can fix the Outlook email sync issue. You need to fix the issue at the earliest to avoid further damage. The folders marked with Outlook IMAP (This Computer Only) are not being synced back to the mail server.In such an instance, Outlook won't let you receive and send emails from your Outlook profile.
In Account Settings, just click Data Files Open Outlook -> File tab and select Account Settings For these just follow these steps: If the number of items differs in both the sections then, you will have to verify the profile settings. Change Profile Settings To Sync OutlookIf the number of items in the Server folder contains section (is same as) with that of in the Offline folder, your Outlook folders are properly synched. To check whether your OST file is being synchronized or not follow the below steps:If you are not aware, all the Imap accounts in Outlook will sync with the Online serverStep 1: Open Outlook and right-click on any of the folder present in your Inbox, Sent Items, Drafts, etc.Step 2: Select Properties and click on Synchronization tab and look for Statistics for this folderStep 3: Now, check the stats of the Last Synchronized data.If the statistics are not recent, then follow the troubleshooting methods Outlook OST file is inaccessible to fix the sync error.
Just make sure that the box next to Use Cached Exchange Mode is selected and then click OK After completion, just click the Email tab -> Mailbox – account name, and click Change If it’s not, then make it as default.
You might not be able to see this folder unless you set it as visible. Empty The "Sync Issues \ Local failures" FolderIf you cannot at all synchronize any of the Outlook folders then, try to empty the Sync Issues \ Local Failures folder in your Outlook. Follow the steps given to know how you can re-synchronize Outlook.Step 1: Click on Tools tab and select Options.Step 2: In the Options dialog box, click on the Mail Setup tab.Step 3: Check the Send immediately when connected box in the Send / Receive section.Step 4: Click Send/ Receive tab and select Perform an automatic Send / Receive when existing.Step 5: Click the Close button to exit the window and then OK.This method will quickly fix the Outlook email sync issue. Re-synchronize Outlook folders To Email Sync IssueRe-synchronizing your Outlook folders can quickly fix this error.
Pst file with the Microsoft Exchange Server mailbox. For this, you have to first rename the old OST file, create a new one and then synchronize the new. To fix this, you will have to create a new OST file and try to re-synchronize all the folders. Fix your OST file To Repair Outlook Email Sync IssueIf this fails to solve the issue then your OST file may be corrupt.

At such a time remember that fixing error 0x800ccc0f in Outlook is easy. This generally can happen while sending/receiving an email.
