When you click on the Hidden Tab in properties you can choose the expression .There you can give custom expression like iif(parameters!parameter.value=nothing,true,false)

this gives if no parameter is selected hide column...

Use JOIN(Parameters!Parameter.Label," / ") to separatae them by "/" or ","

Thanks a lot,it worked

TiffinyJannetBlack,

I think rhe folder folder security works.Can you please tell me how could I set the parameters based on the folder.

Thanks

I have given hidden expression as

IIF(Parameters!PRODUCT.Value(0)="product1",false,true) for first column

IIF(Parameters!PRODUCT.Value(0)="producr2"",false,true) for second column

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.

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IIF(Parameters!PRODUCT.Value(0)="producrt..n"",false,true) for n th column

This works well if one parameter is selected.But when I select more than one...

Roger ,

Thanks for the reply.

I tried using the expression

=iif(Parameters!product.Value(0)="column1",false,true)

But I got an error index was outside of the bounds of array.

Any ideas,

Thanks

Thanks for your reply but how do you redirect to the report based on userid.

Thanks Samuel.It worked .Thanks for your help