Microsoft CRM 2011 allows XRM services that use application/soap+xml content type.

When you install Microsoft CRM 2011 in an IFD / hosted environment, it is smart enough to automatically configure IIS gzip compression on the website.

What it does not do, is configure the

C:\Windows\System32\Inetsrv\Config\applicationHost.config

file to compress XRM calls out of the CRM database.

In a test we were performing for an update to our Microsoft CRM 2011 Portal technology, we found that retrieving a list of around 20,000 items returned a 19 MB data package without gzip dynamic compression. Not huge but pretty big! What amazed us was that after enabling dynamic compression on the XRM data, this reduced from 19 MB to 890 KB, a huge performance improvement!

We also noticed that the Microsoft Hosted CRM 2011 service already has this compression enabled, so we figured if it is good enough for them, then we should give it a shot.

How to Enable XRM gzip Compression in IIS

Navigate to: C:\Windows\System32\Inetsrv\Config\applicationHost.config

and open it in your favourite editor.

Search for the Section: “<httpCompression directory=”

And in that section you will probably find an entry that looks like this:

<add mimeType='application/x-javascript' enabled='true' />

Below that, add the following:

<add mimeType='application/soap+xml' enabled='true' />

So the file looks like this:

Note: We are making the assumption that you are on Windows 2008, and that CRM 2011 was successfully installed, and that this in turn enabled IIS compression on the Microsoft CRM website.

These steps should massively improve data access to CRM using XRM calls.