The question has recently come up, what about password expiration used for Run As Account (and action account) credentials? If you are using Local System, there is no password to expire. If you specified a domain account, we have you covered (for the most part).
When you specify a domain account, Operations Manager 2007 will monitor the expiration policy for that account. When the password for your domain account is about to expire, a monitor in the Operations Manager Management Pack changes to yellow and a warning alert is generated. Hopefully before the password expires, you change the password in the domain account and make the same password change for the Run As Account (or action account) in Operations Manager.
So what happens in Operations Manager if the password for the domain account expires? Pretty much the same experience if your password expires. Without the proper password, you, and the Run As Account or action account will not be able to log in and perform any work. If the password does expire, the monitor in the Operations Manager Management Pack goes from yellow to red and an alert is generated.
So what happens if Operations Manager is unable to monitor password expirations? There is another monitor in the Operations Manager Management Pack that checks to see if Operations Manager can check password expiration dates and if not, the monitor changes to yellow.
So, to keep Operations Manager 2007 running smoothly, keep your passwords up to date.