How can i check the right list

Hello, dear helpers,

If the User has opend session.FindById("wnd[0]/usr/cntlCC_REP_****/shellcont/shell/shellcont[1]/shell") - This is the wrong list.
and  the User has marked lines in the wrong list there is an error in this Code

selrows = session.FindById("wnd[0]/usr/cntlCC_REP_****/shellcont/shell/shellcont[0]/shell").selectedRows

error:"The control could not be found by id."

How can i check the right list?

look at shellcont[0]  / shellcont[1] in the code

One solution is with "On Error Resume Next"

but i looking for a direck Check, similar as

myfindbyid= session.getFindbyIdName

Regards,

Emil