How to upgrade the Kernel

Hi Guys,

first of all I want to say Hello to all of you This is my first post.

I am also quite new to the NetWeaver Administration. So please be patient

I want to upgrade our Portal to 7.4 SPS13 and it worked on all test instances but of course there is a problem on our production one.

In phase 'Specify Credentials' the following happens:

Error while detecting GLOBAL directory using the SAPControl. Sapcontrol client could not perform action get parameter value on instance 1 Return code condition success evaluated to false for process sapcontrol for action get parameter value.

I already searched for a solution and it seems that a upgrade of the Kernel will solve it.

So I also searched for how to upgrade a Kernel but I couldn't find sth that helped me doing this.

So could you please tell me how to upgrade the Kernel of a SAP NetWeaver 7.4 AS Java System?

Best regards

Dominik Aigner