Unable to start queue manager :An internal WebSphere MQ error has occurred on queue manager

If u r not able to connnect to ur Queue Manager in MQ Explorer, then I have a soln for it or if the queuemanger doesnt start after log in.

Try this out.

In Control Panel --> Administrative Tools --> Component Services --> Console Root --> Component Services --> Computers --> My Computer --> DCOM Config --> IBM MQ Series

Right Click that and select properties. In that u have Identity Tab, in that it there will be a question "Which user account do you want to use to run this application?" In that currently it will be selected as This user. Instead select The launching user and give apply and Ok. Then log off and log in and again retry ur process.

WMB password change Issues

Below is the solution to fix broker password change.

1. Fix DB2 services – The easiest way to do this is switch to services view in Windows and spot the services that are failing to start. Next right click these services and from the context menu select properties. Select the Log On tab and change the password used for these services. Please note that some services use the local system account while others use a selected account and it is these services which use a selected account that fail. (I don’t know why services use a different approach as of now so if you know I would appreciate if you can tell me)
2. Next you need to fix the service password for your configuration manager. For this you need to issue amqsichangeconfigmgr -a . Start your configuration manager by issuing a mqsistart command following this.
3. The last piece you need to fix is your broker instance. For this you need to fix both service password and data source password. Issue a mqsichangebroker -a -p . Start your broker instance by issuing a mqsistart command.