Object required error

Dear ALL

I trying to make a code that go through each excel file in folder and change background to no fill,the code runs but after some times having error object required

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Thanks
farrukh

You have an undefined variable wks in

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A good way of spotting these is to add the following line at the top of the code

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This will cause a compile error and highlight the problem when an attempt is made to run the code.