How to change agent manager service account ?

Hi 

    install agent manager require a domain account for service account, but some resaones that I need change this service account.

I try to add new account in agent manager [Access configuration] ==> [OnePoiintOp System] and direct change 3 agent manager's services.

but these services could not start well.

I try to re-run setup.exe to modify, but it does not show the serice account configuration to modify...

How to ler me modify it correct ??

Thanks!!

Wencheng