Registry key: HKCU\SOFTWARE\Microsoft\Terminal Server Client\Servers\<IP>
Overview
The Terminal Server Client\Servers registry key tracks the remote hosts the
associated user connected to (from the local system) using the built-in
mstsc.exe Remote Desktop client. Remote hosts are only added if the remote
host screen was reached, i.e. Network Level Authentication succeed (if the
remote host requires NLA) and the certificate warning has been accepted (if a
warning was displayed).
Entries are added / updated in near real-time.
Information of interest
Each remote host is referenced as a dedicated subkey under the
Terminal Server Client\Servers\<IP> registry key. This subkey is named after
the IP address of the remote host.
For each host, its dedicated subkey references the eventual saved username for
the connection in the UsernameHint value.
Additionally, the last write timestamp may be an indicator of the first access to the remote host (but may have also be updated for various other reasons).
References
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