Unable to open mail account via web browser for administrator

I have domino server 8.5 installed on windows server 2000. I have setup domino web redirectordatabase to access the mail via browser from remote.

Problem is that when administrator tries to access his mail account via browser he gets an error like

"Error 404

HTTP Web Server: Lotus Notes Exception - Entry not found in index[/dominoredir.nsf?Open]"

where dominoredir.nsf is the web redirector database.

This problem is only for administrator account.

while all other accounts are able to access via browser.

But from Lotus Notes client admin is able to access is mail account.

I tried replace design, fixup, and compacting

on the admin mail file but problem is sustain.

Please suggest any solution.