Consider the following scenario. You are running a 32-bit version of Microsoft Internet Explorer on a computer that is running a 64-bit version of a Microsoft Windows operating system. You enable the Make proxy settings per-machine (rather than per-user) Group Policy settings. In this scenario, you cannot access the Internet through a proxy server.

Consider the following scenario:

• In Windows Media Player, you enable the Use proxy settings of the Web browser option. (This is the default setting.)
• Your installation of Windows Internet Explorer uses a proxy server to access certain types of URLs.
  In this scenario, Windows Media Player does not use a proxy server as expected to access the same types of URLs. Therefore, Windows Media Player cannot load the content from these types of URLs.

  For example, in Internet Explorer, you add *.server to the Exceptions list in the Proxy Settings dialog box. However, Windows Media Player may unexpectedly bypass Web sites whose URLs contain the following:

  *.server*
  *.server.*

  When Internet Explorer accesses these URLs, it uses the proxy server as expected.

You are using a proxy script to determine the proxy server settings for a connection in Windows Internet Explorer 7, Microsoft Internet Explorer 6 Service Pack 2 (SP2), or Internet Explorer 6 Service Pack 1 (SP1). However, after the proxy script is downloaded from the server, the proxy server settings in Internet Explorer are not set correctly. You may have to manually configure the proxy server settings.

Consider the following scenario.

• On a Windows Vista-based computer, you do not configure a proxy in Windows Internet Explorer.
• You use Web Distributed Authoring and Versioning (WebDav) to access a fully qualified domain names (FQDN) site.

In this scenario, you are prompted to enter your credentials, even though the user account that you are using has sufficient permission to access this site.

For example, when you open a Microsoft Office file from a Microsoft Office SharePoint site by using 2007 Microsoft Office on a Windows Vista-based client computer that has no proxy configured, you are prompted for authentication.

Note: This problem does not occur on a Windows XP-based computer.

When you try to open an FTP site by using a Web proxy in Windows Internet Explorer 7, you cannot open the FTP Web site. This behavior occurs if the Web site URL contains the following entry:

domain\username

You may be unable open the FTP site even after you replace the backslash (\) by using its URL-encoded form (%5c).

When you try to connect to the Internet from a Windows Vista-based computer that uses a local proxy autoconfiguration (.pac) file, the proxy server is not detected successfully. Therefore, you cannot connect to the Internet.