ascentium | Compression, compression, who turned on the compression?

For those of you still using Internet Explorer 6.0 SP1 or SP2 and are trying to make use of Microsoft Dynamics CRM 4.0, you should be aware of a rendering issue that IE 6 has. The issue results in pages that appear partially rendered and may look something like this:

Besides the 8-bit color rendering, you can obviously see that the page looks a bit off. The reason for this is that the dynamically generated style sheets that CRM produces from pages like global.css.aspx are not rendering correctly.

Here are some of the known issues:

Internet Explorer does not correctly decompress data that uses the GZIP data compression method: http://support.microsoft.com/kb/837251

Internet Explorer 6.0 Service Pack 1 may display a blank Web page after you select Auto-Select encoding: http://support.microsoft.com/kb/870863

Internet Explorer May Lose the First 2,048 Bytes of Data That Are Sent Back from a Web Server That Uses HTTP Compression: http://support.microsoft.com/kb/312496

Internet Explorer may not decompress HTTP content when you visit a Web site: http://support.microsoft.com/kb/871205

Compressed pages that are read from the cache may not be displayed correctly in Internet Explorer 6 on a Windows XP SP2-based computer: http://support.microsoft.com/kb/954078

As you can see there are a lot of bugs when it comes to HTTP compression and IE 6.0. Even though most of these KB articles refer to IE6 SP1 and lower, this appears to still happen in IE6 SP2 (Under Windows XP SP2 and Windows Server 2003). The build of IE I was testing was: 6.0.3790.3959.

I unfortunately could not try Windows XP SP3 in the environment where we were testing, but you might consider that as it contains many hot fixes related to IE6 and rendering. The errors also did not occur in IE 7. The other workaround is to simple disable HTTP Compress within IIS.

From INETMGR, you can get here by right-clicking on the “Web Sites” folder and going to properties, then the Services tab.

More information on IIS6 and HTTP Compression can be found here:

http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/d52ff289-94d3-4085-bc4e-24eb4f312e0e.mspx?mfr=true

Cheers,