@echo off
:: RegEdit can only export into a single file at a time, so create two temporary files.
regedit /e "%CD%\environment-backup1.reg" "HKEY_CURRENT_USER\Environment"
regedit /e "%CD%\environment-backup2.reg" "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment"
:: Concatenate into a single file and remove temporary files.
type "%CD%\environment-backup1.reg" "%CD%\environment-backup2.reg" > environment-backup.reg
del "%CD%\environment-backup1.reg"
del "%CD%\environment-backup2.reg"