Hi,
previouspage is null because the page where error occured redirected to error page.
only page A post data to page B then you can access PreviousPage in Page B.
but from server variable "Referer" you can find name of previous page.
what you can do is for each master apge write erro event
Master_Error()
{
//Here you can redirect to the page you want to. If you error page is doing more than redirecting then then
redirect to error.aspx like error.aspx?name=MasterPagename
then you can use query string value in error.aspx.
}
Hope it helps.
Thanks,
Kiran
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