Hello again,
I want to add some info to this issue, what i can't hide/show in reportviewer are row group based columns, simple columns works fine.
What I can do in designer is to set visibility based on parameter for header and details of a group, and it works in designer but not in reportviewer.
In other words, i can show/hide a column but no a column which show row group data.
Also I can't hide/show header and details of a row group, this only works on designer preview but not in reportviewer.
Thanks,