This is more an IIS related error than an SharePoint error, but due to the fact that I received this while building a SharePoint Web Application I thought it might be relevant.

I was recently involved in an virtualization project where we moved all the companies servers to a hosted environment running in the cloud and at the same time we virtualized all the production servers to run as VM’s using Hyper-V. During this process we ended up re-installing and configuring a number of different servers including our ISA 2006 firewall server and this is where the problem occurred.

Some of the existing Web Applications also experiences this problem when attempting to editing column settings on a list.

After doing some research I find a blog entry that explain how to fix this using SSRS and since this issues was related to ISA I thought that it would be worth a try. The steps are outlined below:

1. Start the ISA Server Management tool.
2. Expand “ServerName”, where “ServerName” is the name of your ISA Server computer.
3. Click Firewall Policy, click the Web publishing rule that you created to publish the MOSS server and then click Edit Selected Rule.
4. Click the Traffic tab, click Filtering, and then click Configure HTTP.
5. Click to clear the "verify normalization" check box, and then click OK two times.
6. Click Apply to update the firewall policy, and then click OK.

I hope this saves other people some time and effort in the future.

Reference Blogs:

http://blogs.msdn.com/jay_akhawri/archive/2007/07/14/error-code-500-internal-server-error-the-request-was-rejected-by-the-http-filter-contact-the-server-administrator-12217.aspx

Related Blogs:

Fixing a DCOM error on Windows Server 2003

Resolving a DCOM Error 10016 (Local Activation) on SharePoint

ASP.NET error registering with IIS

Getting "Debug Info" for a SharePoint error