SAP Note 25863 - Error KC028 when creating cost centers/elements

Symptom:

When creating a cost center or a cost element, the error KC028 occurs: You are not in the home system of controlling area &
Creating is not possible.

Cause and prerequisites

In distributed systems, cost centers or cost elements can be created only in the logical system assigned to the controlling area. However, the controlling area is obviously assigned to a logical system other than the client that you are working in.

Solution
Please check whether the preconditions for the error message are applicable, that is, whether you should actually be working with distributed systems which are networked with each other by A.L.E. in your installation.
If this is not the case, the entries that do not match for the logical systems probably resulted from a client transport. In this case, please change the logical system of the controlling area so that it matches that of the system (in table T000). Alternatively, you could simply delete the controlling area (set to SPACE). To do this, you must change the basic data of the controlling area in the maintenance transaction.
If this is not the case, you can create cost centers and master data only in the logical system of the controlling area.

Additional key words

Transaction KS01, KA01, KA06