I have tried changing the SQL Server Agent account first through Configuration Manager. However after entering the new service account name and password and hitting the apply button I get the following error -
'The specified network password is not correct.'
Having checked the password is correct I am at a loss as to what is wrong. I am an admin on the box but not a domain admin, but I have changed this before from the default to using a gMSA account, however now we are having to go with just a normal domain service account.