Occasionally you need to get something done on a remote computer (or a clients computer) but the computer doesn’t have an easy way for you to connect to it. Luckily, if you have admin rights to the remote computer, you can still connect without needing to turn on remote desktop before hand. To do that you will just need to download one thing. PsExec is a Microsoft tool part of their PsTools. PsExec is a portable program that you can copy to any USB drive or run it anywhere from your hard drive. Once you have PsExec download you just need to open a command prompt and browse to the folder with psexec.exe. Once the command prompt is open, type in this command and it will enable remote desktop on the machine you specify.
psexec \machinename reg add “hklmsystemcurrentcontrolsetcontrolterminal server” /f /v fDenyTSConnections /t REG_DWORD /d 0
Make sure you replace “machinename” with the computer you are trying to control remotely. Once this command has run you should now be able to connect with mstsc.exe to the remote computer.