Permission to User Control

Question

Dear Sir,

I have an html page that use a control in an assembly dll devellopped in c# - vs2005.

I haven't signed it.

It works ok in iis.

When I added an extra method to write a file on the client pc I got problems with the following error:

Messaggio: Richiesta di autorizzazione di tipo 'System.Security.Permissions.FileIOPermission, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' non soddisfatta.
Linea: 94
Carattere: 1
Codice: 0
URI: http://localhost/privacy/cards.htm


Which is the easiest way to make it works ???? Please give me instructions about it. I would like to avoid complicated authorization to make client side.