Comments on: Exchange 2010 Service Pack 3 OWA and Outlook Anywhere error HTTP 440 – 440 response was received from Unknown http://exchangeblog.pl/en/2013/03/exchange-2010-service-pack-3-owa-and-outlook-anywhere-error-http-440-440-response-was-received-from-unknown/ Blog technologii MS Exchange Server Thu, 20 Aug 2015 06:37:04 +0000 hourly 1 https://wordpress.org/?v=4.0.38 By: Rodney http://exchangeblog.pl/en/2013/03/exchange-2010-service-pack-3-owa-and-outlook-anywhere-error-http-440-440-response-was-received-from-unknown/#comment-94038 Sun, 01 Sep 2013 06:56:15 +0000 http://exchangeblog.pl/?p=3425#comment-94038 In the hopes of helping the next person, I was on Exchange SP2 Rollup 7 and I went to Exchange SP3 and Outlook Anywhere broke.

The cause was not the above, not corrupt web.config files (the other common cause) – it was that SP2 was using ASP 2 and then SP3 uses ASP4 for HTTP activation (not required pre SP3)..

I eventually figured this out and fixed it with this command:
c:\WINDOWS\Microsoft.NET\Framework\v4.0.30319\aspnet_regiis.exe -iru

]]>