Hello faraz240, I'm Didi, an independent advisor.
To fix Remote Desktop "An internal error has occurred" error try the procedures given in this tutorial : https://www.kapilarya.com/fixing-remote-desktop...
If it doesn't work go to your Documents folder, make sure you have enabled the option to see hidden files and delete the "Default.rdp" file.
Empty your recycle bin, restart your computer and check if the issue is fixed.
Regards,
Didi
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