To set the default startup directory when executing admin power shell, use the following command (currently I have my directory set to c:\dropbox\dev)

*PowerShell -ExecutionPolicy Bypass -NoLogo -NoProfile -NoExit -Command "Invoke-Expression '. ''%ConEmuDir%\..\profile.ps1''' -new_console:d:"c:\dropbox\dev"

Make sure to make the change on the tasks tab:

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Then set that task as your startup

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