Message: Sys.WebForms.PageRequestManagerServerErrorException: Request for the permission of type 'System.Security.Permissions.FileIOPermission, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.
Line: 604
Char: 13
Code: 0
URI: http://..../ScriptResource.axd?d=mAdX6eEFtP0fcZYXhk1u4DJ_6j8HSI5PEx1ybgDGPhGk60gQGytztK9vHmWQfBxO-EEpbbiyvC_BTg5S0l0T1ukn5JQdidGmndkkfxAGJ_Z6GxeuSKntsZbYeeGW8Ss50&t=633406813064242674

It is a .NET application using the version 2.0 of the AJAX Uploader. My web.config does have an  identity impersonate="true" userName="***" password="***"/>. The uploader has been working fine for months but recently (not sure when) it started failing. My web host has assured me that my user has permissions to write to the file system and that nothing changed on their side. While I do suspect otherwise I am a little confused becuase when uploading files they are able to write to my temp folder but when clikcing on the save button I get the error above.