Hello,
Verify the Network Level Authentication (NLA) settings on both PCs.
When logging in via 'mstsc', if you're prompted to enter credentials before the session window appears, it indicates that NLA is enabled, with authentication occurring between the client and the authentication server.
If the session window appears first (similar to the second picture), then authentication is taking place between your terminal and the authentication server.
For domain users, the authentication server should be your domain controller; otherwise, authentication will occur locally. This information should assist you in further troubleshooting.
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