Diagnosis
You selected a column which you want to remain fixed (along with allpreceding columns) when you scroll the list horizontally. This ispossible only if the selected column and all preceding columns are intheir orginal positions in the table display.
In this particular case, the position of the selected column or one ofthe preceding columns has changed.

Procedure
First, restore the orginal sequence of columns and then fix the desiredcolumns.