replication stopp after change changing SQL Server Agent User

Hi,

I tryed to change the user for SQL Server Agent on my Distributor. We use pushed transaction replications. But after i changed the user, all replications stopped:

ERROR: (from SQL Monitor)

The job failed.  The Job was invoked by Start Sequence 0.  The last step to run was step 3 (Detect nonlogged agent shutdown.).

The new user is a domainusert too, and had administrative rights on the server. I changed the user to start SQL Server Agent on other servers without error.

Can anybody tell me, how to change the user on a distributor, without stopping all replications?

Thanks

Kind regards,

Andreas