Repair 0x800CCC90 Error

Fix Error Code

What is the error 0x800CCC90?

Error 0x800CCC90 is a usual Outlook error. This error shows that the Outlook has failed to connect to the mail server which switches and manages the sent and received emails. The error message is displayed in the following format:

“There was a problem while logging into your mail. Your User Name was rejected.”

This error limits your capability to send and receive emails on Outlook. If you greatly communicate at workplace using your Outlook account, this error might slow down your work efficiency and performance significantly. Therefore it is desirable to fix it immediately.


Download available to completely repair Error 0x800CCC90

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0xError Causes

The error 0x800CCC90 is activated many reasons including but not limited to:

  • Failure of POP 3 Server
  • Registry issues- Invalid Entries
  • Viral infection
  • PST File Corruption
  • Authentication issues

Additional Information and Manual Repair

To determine error 0x800CCC90, try the methods given below:

Method 1 – Adjust the Authentication Settings

To determine the error 0x800CCC90, adjust the authentication settings. Here’s what you need to do:

  • First go to ‘Tools’ tab and select ‘Accounts’ option.
  • Once you select the account option, an internet accounts box will appear on the computer screen.
  • Simply double click on the account property box after that go to the server tab and click on it.
  • Check the box that says My Server Requires Authentication.
  • Click on apply to accept changes tab to save changes and close the window.

To activate changes made, restart Outlook and then try sending emails again.

Method 2 – Download a PST Repair Tool

If the error is activated by PST file corruption, then the best way to determine it is to download PST repair tool. Download PST repair tool from a trusted website. Run it on your system to fix PST file issues and determine error 0x800CCC90.

Method 3 – Scan for Viruses

Other way to determine this error is to scan for viruses. Viruses normally enter computer systems via phishing emails or while downloading files.

You may not know this but viruses may be disturbing your PC. Because of viruses, errors like error 0x800CCC90 can also be activated. Therefore install an antivirus to scan and remove errors on your Personal computer.

Method 4 – Clean the Registry and Remove Invalid Entries

Because of  poor PC maintenance, invalid registry and mis-configured entries may be stored in the registry. That type of  entries may lead to Outlook errors also. So as to resolve you must clean the registry and remove these entries right away. Download a registry cleaner to fix the error.


Whether the error is activated by viral infection or registry issues, it is suggested you download only Total System Care. This is one stop solution to determine all PC connected errors. This software is deployed with 6 scanners along with an antivirus ,registry cleaner and a system optimizer.

It is user-friendly and has easy navigations and also well-matched with all Windows versions including Windows 7, 8, 8.1, XP and Vista. In just a few clicks this software determines practically all types of PC connected errors including error 0x800CCC90.

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