Event ID 1006 means "The processing of Group Policy failed. Windows could not authenticate to the Active Directory service on a domain controller. (LDAP Bind function call failed). Look in the details tab for error code and description."
And ErroCode 49 is "Invalid Credentials".
The account listed is sometimes the computers SYSTEM account and sometimes my useraccount. The same second or about a second after Event ID 1006 another Event is logged, ID 1500 or 1501 which means succesful processing of the Group Policy, again using the same useraccount.
Why does the client think my credentials are bad from time to time? Should I worry or is this just a "feature" to ignore?