How are instance lists remembered?
In Windows applications instance lists are remembered. To find out where they are kept first find out the "Internal Identifier" of the business object involved, say, BUSINESSOBJ_N.
Then search for files with names BUSINESSOBJ_N_Part_1.Lst and BUSINESSOBJ_N_Part_2.Lst in a temporary directory on your system.
These files store the instance list details of BUSINESSOBJ_N between Framework executions. They can be deleted at any time to cause remembered instance list details to be lost. You should always delete both files (Part_1 and Part_2) together.