When trying to connect to a server or machine via Remote Desktop Connection you will get the below error which is strange as one would normally connect without any issues.
“Remote Desktop Connection
An authentication error has occurred.
The function requested is not supported
Remote computer: XXX.XXX.XXX.XXX”
After some research I found that this is due to a Windows Update patch which was released recently that is CVE-2018-0886 for RDP. So if the workstation was updated and the server was not yet.
There are two options for this.
Patch the server with the CVE-2018-0886 (Recommended)
Update the policy on the local computer (Not recommended but in case of emergency)
On the computer open Group Policy
Go to Computer Configuration > Administrative Templates > System > Credentials Delegation
Change Encryption Oracle to Remedition to Enabled
Change Protection Level to Vulnerable
Open MSTSC and you will be able to connect to the server.
When you open a specific attachment in Outlook you might get the error saying Outlook blocked access to the following potentially unsafe attachments. Here’s a some solutions to help you unblock attachments in Outlook
Make sure that Outlook is closed. Open Registry and go to the below area depending on your office application version
Microsoft Office Outlook 2010
Microsoft Office Outlook 2007
Microsoft Office Outlook 2003
Microsoft Outlook 2002
Microsoft Outlook 2000
Create a new String Value and enter
As the value enter the extension of the file example
.pptx, if you want to add multiple extensions, seperate them with a semicolon like this,
Close regedit and open Outlook
If this doesn’t work then you might have an update that blocks as Microsoft have released a patch which blocks safe files.
If you do have the below updates according to the Office version, remove them.
Outlook 2007: KB3191898
Outlook 2010: KB3203467
Outlook 2013: KB3191938
Outlook 2016: KB3191932