Friday, November 20, 2015

HTTP 400 Bad Request When Proxying a Different Version of Exchange

As a part of an Exchange 2010 to 2013 Upgrade project I am working on I hit a sporadic issue of users not able to access Outlook or getting an "HTTP 400 Bad Request" Error after signing in to OWA.

In the midst of doing some quick searching on the error as I knew it was user issue and found this article from Microsoft about token bloat.

I had found several other article about token bloat and some of the users having the issue had 100+ groups. I followed the guidance and added the follow Registry Keys on the Exchange 2010 Client Access Servers.

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\HTTP\Parameters

MaxRequestBytes DWORD 65536 (Decimal)

MaxFieldLength DWORD 65536 (Decimal)

Once added you will need to restart the sever for the changes to take effect.

The above change will increase the header size to 65KB which is the max value

I would recommend that if you are in a large enterprise environment or if your users are a part of a large number of groups that you set these values prior to swinging your namespace to the newer version of Exchange.

Friday, November 6, 2015

Exchange 2013 CU10 Application Event Warning 1310

Working through a fresh install of Exchange 2013 CU10 I noticed within my event viewer an application error with the source of ASP.NET 4.0.30319.0 and the event ID of 1310 after doing some looking I found thanks to Garry Cooper over at Exchange Masters blog found that this looks to a little known installation bug. I as able to resolve by copying the C:\Program Files\Microsoft\Exchange Server\V15\ClientAccess\SharedWebConfig.config file from a good install to the other servers that were missing the file.