Object reference not set to an instance of an object in SharePoint 2010

I was going through the server Event log the other day and noticed the following error.
 
The Execute method of job definition

Microsoft.SharePoint.Administration.SPPasswordManagementJobDefinition (ID 2c784c63-26c9-4e2c-8dbf-f347222ed56b) threw an exception. More information is included below.

Object reference not set to an instance of an object.
 
Then I went to SharePoint Central Administration, Security, Configure Managed accounts and the page displayed “Object reference not set to an instance of an object” error message.
 
Figure 1


 
Some users suggested to remove and recreate the manage account using PowerShell command Remove-SPManagedAccount. That doable, but I found a better solution that does not require to recreate the managed account here. First, I ran the PowerShell command Get-SPManagedAccount to find out the account that caused the problem. Then I used the PowerShell command from here to remedy the problem.
 
Figure 2


 
Learn more about service and managed service Accounts from here.