Indirect function problem

Hi all,

I've been trying to reference to cells in another open files and have been attempting to use the indirect function. =INDIRECT("["&G7&"]SHEET1!F4")
Where G7 is the file name e.g. Book1.xls and F4 is the cell from which i wish to reference from. However, I have a macro which generates the list of open files in columns. The indirect function returns a REF! when i link my indirect functions to the results of the macro and the indirect function only works when I manually type in the file name. This does not help as the initial intention of creating a macro is the automate the process (to capture data from cells of workbooks which are opened by a user). I do not understand why this situation is occurring. I appreciate if any help or assistance of any sort can be rendered.

Shawn