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Read more:- Fix Outlook Error 0x80040115

Method1:
Open the Control Panel and the Mail item.
Click on Show Profiles.
Now, select your profile and hit a click on Properties.
Click on Email Accounts.
Select the MS Exchange Server account and click on Change.
Click on more settings in the dialog box containing your username and mailbox server.
Now, click on the security tab in the Microsoft Exchange dialog box.
Choose the Encrypt data between Outlook and Microsoft Exchange check box option. Click OK.
Method2:
Start your system and log in as an administrator.
Go through the navigation, Start→All
Programs→Accessories→System Tools→System Restore.
In the new window, select the option”Restore my computer to an earlier time” and hit Next.
From the restore point list, select the most recent system restore point and hit Next.
Click Next on the confirmation window.
Restarts the computer when the restoration is finished.