Change action account SCOM Gateway Server

If you want to use a other (not system) account, you must verify if the account exsist under:
Administration -> Run As Configuration -> Accounts -> Action Account
If not make a new one.

Then:
Open Administration -> Run As Configuration -> Profiles -> Default Action Account
Rightclick Properties -> Run As Accounts “Edit” the one for your gateway server to the one you have created or the local system account.