Assignment error: Overwriting of a protected field.

Hi,

While updating the Supplier Shutdown Profile using Function Module in report program, we have to clear the global variable used in the function group of that FM.

The global variable is LAST_VIEW_INFO. We have tried to access the global variable outside the FM using the field symbol.

Like:

Field-symbol: <fs>  type any.

assign '(functiongroupprogramname)LAST_VIEW_INFO' to <fs>.

if <fs> is assigned.

<fs> = space.

endif.

Here assignment is done successfully, however when the <fs> is cleared, we get dump as "Assignment error: Overwriting of a protected field".

Is there any other way to clear or access the global variable outside the FM in custom program ?