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Archive for the ‘CAS’ Category

The WinRM client cannot process the request….The content type is absent or invalid

Posted by Milind Naphade on 17/12/2010

One of my customers logged a case yesterday asking to fix their EMS issue on their only Exchange 2010 server. They were neither able to open the EMC on the server nor from a remote computer. The error that was shown in EMC was:

"Connecting to remote server failed with the following error message: The WinRM client cannot process the request. It cannot determine the content type of the HTTP response from the destination computer. The content type is absent or invalid."

Of course I followed the Exchange Team’s article http://msexchangeteam.com/archive/2010/02/04/453946.aspx to fix the WinRM connectivity issues but it didn’t work unfortunately. After checking all permissions and settings on Powershell virtual directory, I downloaded and ran recently released EMTshooter.ps1 powershell script from http://msexchangeteam.com/archive/2010/12/07/457139.aspx but it wasn’t able to fix the problem either.

Another symptom that I noticed is when I double click the Modules in Powershell virtual directory, I get an error saying,

This configuration section cannot be used at this path. This happens when the section is locked at a parent level. Locking is either by default (overrideModeDefault="Deny"), or set explicitly by a location tag with overrideMode="Deny" or the legacy allowOverride="false". 

Config File \\?\C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\Powershell\web.config

After opening the web.config file and looking in the file carefully I noticed that the file has two environment variables used %ExchangeInstallDir% and %ExchangeInstallDirPath%. These variables are supposed to be registered in advanced system properties page of the operating system. In my case the physical path for %ExchangeInstallDirPath% was missing. This path should be the actual installation directory of your exchange server (Normally C:\Program Files\Microsoft\Exchange Server\V14\)

Once you open system properties and create the missing environment variable %ExchangeInstallDir% or %ExchangeInstallDirPath% depending upon the situation you have and point the physical path to C:\Program Files\Microsoft\Exchange Server\V14\ (Note the \ after directory V14) You should be able over come the error that EMS shows up.

I hope that helps Smile

Posted in CAS, Exchange 2010 | Comments Off on The WinRM client cannot process the request….The content type is absent or invalid

Mystery of Notes in Exchange 2010 OWA

Posted by Milind Naphade on 07/07/2010

I have seen a few questions on Technet Forums recently which were related to Notes section in Exchange 2010 OWA.

The symptom is that a user is not able to create any notes after selecting Notes folder.

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I just learnt that this Notes folder is left behind and will be unsupported in OWA. So, currently there is no way that you can fix this problem and get notes created using OWA. You must use Outlook for doing so.

Posted in CAS, Exchange 2010 | Comments Off on Mystery of Notes in Exchange 2010 OWA

Exchange 2010 CAS Role and High Availability

Posted by Milind Naphade on 21/03/2010

I am working on a Exchange 2010 design these days. The design needs to be in a way so that the maximum availability can be achieved. For Exchange 2010 mailbox server roles I didn’t worry much because a DAG dispersed across the sites can take care of it very well. However, it is a little challenging job to design HA for CAS and HT servers.

If my primary site fails due to catastrophic conditions the Exchange DAG will of course failover to another site where passive copies of my databases exist but what about my CAS and HT server roles. I am least bothered about the HT server roles either because they  have their built in logic to load balance themselves and keep working with just a little modification in my MX records on internet (if at all I have multiple records which are pointing to another server in another site then there is very little left that I need to worry about, so this functionality eliminates the need of Exchange 2010 HT failover or high availability. Needless to say; this is the perfect solution in case I have already setup my internal settings correctly). Now, let’s think of CAS server role. CAS does not have any built in logic to load balance between themselves unless they are a part of a CAS array and/or NLB. If one server fails the other server can still work using the NLB. Yet the question remains unanswered, how do I achieve maximum availability to configure HA between my CAS server roles in case of a complete site failure?

As I mentioned above, they don’t have any built in logic for this but of course, there are ways around to configure it with a little additional efforts. So what do in this case? A simple DNS modification would serve the purpose.

Let’s us say I have two sites involved in this scenario. Site A and Site B, Site A is my primary site. Where:

  1. MAIL.COMPAY.COM is the name of my CAS Array in Site A.
  2. MAIL.COMPANY.COM is an internet facing site.
  3. INTERNAL.COMPANY.COM is the name of CAS array in another site.

Due to some reasons the whole of Site A goes down and CAS servers are totally inaccessible then I change followings:

  1. Change the IP address of mail.company.com to point to the new IP address of INTERNAL.COMPANY.COM on internal and external DNS servers both. Revert these changes when your site is back online.
  2. Configure Outlook to “on fast network, connect via RPC, on slow network, connect via HTTPS” – This way outlook uses Outlook Anywhere if it connects to discover the RPC endpoints. This works perfect with Outlook 2003 and Outlook 2007 in cached mode.

In this solution the only drawback is, it needs the time to replicate the changes across the globe (on both internal and external DNS servers). If you have SCOM then it makes your life much easier to handle this situation.

Bottomline, for CAS servers in Exchange 2010, using the CAS Array capabilities of Exchange 2010 will allow you to create a CAS Array in each Exchange site and then configure the system to major an array object in your primary site resolve to a CAS Array in your secondary site until the primary site is back up and running.

Please do let me know if you think I have missed on anything in above. I would be glad to learn if you can think of any better solution than it 🙂

EDIT: Elan Shudnow has two excellent articles covering the considerations related to CAS HA. Read more here:

http://www.shudnow.net/2010/03/17/exchange-2010-rtm-high-availability-load-balancing-options/

http://www.shudnow.net/2010/03/04/exchange-2010-rpc-client-access-service-and-multiple-sites/

Posted in CAS, Exchange 2010 | Tagged: , | 3 Comments »

Changing OWA time out on an Exchange 2007 and 2010 Computers

Posted by Milind Naphade on 22/10/2009

Exchange Server 2007 OWA will automatically time out for the security purposes. This feature has been designed to restrict unauthorized access to any mailbox when the user is using a public or shared computer. You can select this option before you logon to your mailbox:

Though this feature is good for security reasons it may be annoying for many users who use OWA regularly and they may not want to enter the password several times after the time out. This can settled down with a simple registry tweak on the CAS box that runs your Internet facing OWA site. This can be done by following registry modification.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeOWA

Name: PublicTimeout

Type: DWORD

Value: {value in minutes} (This value is 15 minutes by default)

image0041255958448201

The above suggestion applies only when the user selects the Public Computer option from the OWA logon screen. For the user who select the Private Computer from the logon screen you might want to modify:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchange OWA

Name: PrivateTimeout

Type: DWORD

Value: {value in minutes} (This value is 8 hours by default)

If you don’t see the DWORD values named, PublicTimeout and PrivateTimeout then you have create then manually.

Posted in CAS, Exchange Server 2007 | 2 Comments »