Three common problems when connecting via RDP to a server: Ctrl+C/Ctrl+V does not work between the local PC and the server, an unknown certificate warning appears, or authentication fails. Each one is a 2–5 minute fix once you know where to look.
Clipboard copy-paste not working between PC and server
The most common RDP complaint: text copied on the server will not paste on the local computer, and vice versa. The cause is almost always the same — clipboard redirection was not enabled when the connection was opened.
How to enable clipboard redirection
Before connecting, open Remote Desktop Connection (mstsc.exe), click "Show Options" → "Local Resources" tab. Under "Local devices and resources", make sure "Clipboard" is checked. If a session is already open — you cannot change this setting without reconnecting.
If clipboard stops working mid-session
rdpclip.exe can hang during an active session. Fix without disconnecting: open Task Manager on the server, kill the rdpclip.exe process, then restart it via "Run new task".
Unknown certificate warning
When connecting to a server without a trusted SSL certificate, Windows shows a warning: "Publisher unknown" or "The identity of the remote computer cannot be verified." This does not always mean the connection is unsafe.
When it is safe to click "Connect"
You are connecting to a corporate server on the local network (IP like 10.x.x.x or 192.168.x.x)
Your administrator confirmed the server uses a self-signed certificate
The certificate fingerprint matches what your admin provided
When you should not connect
The connection was not initiated by you, or the server address is unfamiliar
You are connecting over the internet to a public IP and the certificate unexpectedly changed
The certificate fingerprint differs from what is expected — a potential sign of a MITM attack
To permanently remove the warning for a specific server: install the server self-signed certificate in the "Trusted Root Certification Authorities" store on the local PC, or replace it with a certificate issued by a trusted CA.
Authentication errors
"Wrong username or password"
Check the username format: for a domain server use DOMAIN\username, for a local account use .\username. Also verify Caps Lock and keyboard layout.
Account locked out
After several failed attempts, Windows locks the account per Group Policy. An administrator can unlock it via Active Directory Users and Computers or with a PowerShell command:
Unlock-ADAccount -Identity usernameNLA requires a newer client
The error "An authentication error has occurred" or "Remote computer requires Network Level Authentication" appears when the server requires NLA and the client is outdated. Client-side fix: update Windows. Server-side workaround (if the client cannot be updated): System Properties → Remote → uncheck "Allow connections only from computers running Remote Desktop with Network Level Authentication".
Setting up an .rdp file for automatic resource redirection
If you connect to the same server regularly, save your settings in an .rdp file to avoid manually checking boxes each time. Edit the file in any text editor:
redirectclipboard:i:1
redirectprinters:i:1
redirectsmartcards:i:0
redirectwebauthn:i:1
drivestoredirect:s:
full address:s:10.10.10.10
username:s:DOMAIN\username
prompt for credentials:i:1:i:1 = enabled, :i:0 = disabled. Empty drivestoredirect:s: disables local drive redirection — recommended for security. Save the file with the .rdp extension — double-clicking opens the connection with the correct settings applied automatically.
Need professional help?
If the issue persists, the cause may be server configuration, group policies, or network equipment. English-speaking technician available. IT-Master responds in Odesa within 1 hour, remote assistance also available. Free diagnostics with any service order.