Khắc phục lỗi 502 Proxy Error được không?

Tui vào 1 số web download như: MU,RS,MF thì gặp lỗi sau:

Code:

Network Access Message: The page cannot be displayed
	Explanation: There is a problem with the page you are trying to reach and it cannot be displayed.

Try the following:

    * Refresh page: Search for the page again by clicking the Refresh button. The timeout may have occurred due to Internet congestion.
    * Check spelling: Check that you typed the Web page address correctly. The address may have been mistyped.
    * Access from a link: If there is a link to the page you are looking for, try accessing the page from that link. 

If you are still not able to view the requested page, try contacting your administrator or Helpdesk.

	Technical Information (for support personnel)

    * Error Code: 502 Proxy Error. The ISA Server denied the specified Uniform Resource Locator (URL). (12202)
    * IP Address: 10.16.8.94
    * Date: 6/11/2010 3:36:33 AM [GMT]
    * Server: HN-PRX001
    * Source: proxy

bro nào bít cách khắc phục thì chỉ giúp với nhé!
Note: tui không bít phải post thắc mắc này vào mục nào nên psst vào đây. Mod thông cảm nhé.