How to fix "An authentication error has occurred. The function requested is not supported." in Remote desktop Connection?
This method only fixes for this error below :
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Solutions:
Search gpedit.msc. Then right-click and choose Run as administrator to open Group Policy Editor.
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Go to the following policy path: Computer Configuration → Administrative Templates → System → Credentials Delegation.
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From the right-hand panel, open Encryption Oracle Remediation.
Select Enabled and set the protection level to Vulnerable, and click OK.
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Solutions:
Search gpedit.msc. Then right-click and choose Run as administrator to open Group Policy Editor.
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Go to the following policy path: Computer Configuration → Administrative Templates → System → Credentials Delegation.
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From the right-hand panel, open Encryption Oracle Remediation.
Select Enabled and set the protection level to Vulnerable, and click OK.
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Updated on: 21/06/2022
Thank you!