Client Cannot connect to TFS after installing service pack 1

Recently I have a customer faced an issue that the client cannot connect to the TFS after installing service pack1. This is really weird as we connected to the TFS successfully and created a team project. But after the service pack 1 installation, the client totally cannot connect the TFS.
After troubleshooting for quite a while, only realized that the IIS permission settings have been modified after the service pack 1 installation. At first, I modified the permisson settings on the Team Foundation Server and client ables to connect to the TFS. But there were still red cross on the "Document" and "Report" folder in the team explorer. Finally, only found out that the permission settings on the SharePoint and Report site also have been modified.

This issue occured due to after TFS SP1 installation, the modified permission settings on the IIS manager didn't restore to the default settings.

Here is the solution on how to fix this problem:
1. Go to START > All Programs > Administrative Tools > Internet Information Services (IIS) Manager.
2. Expand Web Sites node
3. Right click Default web site and then select Properties.
4. In the Web Sites Properties windows, select the Directory Security tab.
5. Under Authentication and access control, click Edit
6. Select Integrated Windows Authentication and uncheck Enable Anonymouse access, and then click OK.
7. Under IP address and domain name Restrictions, click Edit.
8. In the IP address and Domain Name Restrictions window, select Granted access, and then click OK.
9. Click OK.
10. Repeat step 3-9 at the Team Foundation Server and SharePoint Central Administration nodes.

Now, you allow your client to access Team Foundation Server, SharePoint and Report site.