"Enable compression using a command line.
a. Open the Command Prompt on the CRM Server.
b. Run the following command:
%SYSTEMROOT%\system32\inetsrv\appcmd.exe set config -section:system.webServer/httpCompression /+"dynamicTypes.[mimeType='application/soap%u002bxml; charset=utf-8',enabled='true']" /commit:apphost
c. Reset IIS for the setting to take effect.
Enable compression by manually updating the ApplicationHost.Config
a. On the CRM Server Navigate to: C:\Windows\System32\Inetsrv\Config\applicationHost.config and open it with notepad.
b. Search for the Section: “” and in that section you should fine an entry that looks like this:
c., Below that, add the following line:
d. Save the file and reset IIS for the setting to take effect.
Note: For additional information about configuring HTTP compression, on TechNet, see the article Configuring HTTP Compression in IIS 7