As you surf the Net, you will undoubtedly find that at times you can't access certain websites. Why? Error messages attempt to explain the reason. Unfortunately, these cryptic messages baffle most people. We've deciphered the most common ones you may encounter. 

400 - Bad Request  

Problem: There's something wrong with the address you entered. You may not be authorized to access the web page, or maybe it no longer exists. 
Solution: Check the address carefully, especially it the address is long. Make sure that the slashes are correct (they should be forward slashes) and that all the names are properly spelled. Web addresses are case sensitive, so check that the names are capitalized in your entry as they are in the original reference to the website. 

401 - Unauthorized 

Problem: You can't get onto a website, because you're not on the guest list, your password is invalid or you have entered your password incorrectly. 
Solution: If you think you have authorization, try typing your password again. Remember that passwords are case sensitive. 

403 - Forbidden 

Problem: Essentially the same as a 401. 
Solution: Try entering your password again or move on to another site. 

404 - Not Found 

Problem: Either the web page no longer exists on the server or it is nowhere to be found. 
Solution:
Check the address carefully and trying entering it again. You might also see if the site has a search engine and if so, use it to hunt for the document. (It's not uncommon for pages to change their addresses when a website is redesigned.) To get to the home page of the site, delete everything after the domain name and hit the Enter or Return key. For example: if the address is:  http://www.allsher.com/english/html/email.htm remove: english/html/email.htm 

503 - Service unavailable 

Problem: Your Internet service provider (ISP) or your company's Internet connection may be down. Solution: Take a stretch, wait a few minutes and try again. If you still have no luck, you may have to phone your ISP or system administrator. 

550 - xxxxxxxxx is not a known user 

Problem: Using e-mail, you sent a note to an e-mail address that isn't recognized at the mail server you've specified. The e-mail note got all the way to the mail server (so that part's right), but you may have entered the user part of the e-mail address incorrectly or the user may no longer have an account on that server 
Solution:
Make sure you entered the correct e-mail user name. If you suspect it's an old address or was mistyped in a note sent to you, try looking up a new address using the person's name. Try e-mail address finding tools. 

Bad file request 

Problem: Your web browser may not be able to decipher the online form you want to access. There may also be a technical error in the form. 
Solution:
Consider sending a message to the site's webmaster, providing any technical information you can, such as the browser and version you use.   

Cannot add form submission result to bookmark list 

Problem: You've just entered a search request and tried to save the result as a bookmark. Though it may appear as a discrete address, the result isn't a legitimate URL, so you can't add it to your bookmark list. 
Solution:
Try saving the result page as an HTML page on your hard disk. Use the Save As command then add the saved page to your bookmark list. Depending on the CGI script behind the query, you may or may not be successful. But it's worth a try.   

Connection refused by host 

Problem: You don't have permission to access the page or your password is incorrect. 
Solution:
Try typing your password again if you think you should have access.   

Error_117 ClearVideo Not Supported in Windows 3.1 or Unix Players. 

Problem: ClearVideo, a RealVideo compression/decompression (codec) library, is available only for Windows 95, Windows NT, and Macintosh Power PC. Video clips created using the ClearVideo codec cannot be played on Windows 3.1 or Unix. 
Solition:
Need correct operating system Windows 95/98, Windows NT or 200 or Macintosh Power PC.   

Error_120 The logical drive chain is incompatible 

Problem: This error occurs under some operating systems when logical partitions are not chained together in the expected order. DOS, OS/2, Windows 95 and Windows NT require that logical partitions be chained together in ascending order. Some other operating systems do not require this. For example, some versions of the Linux FDISK utility chain logical partitions together in the order they are created. This error message identifies a very dangerous situation; using the DOS FDISK in this situation can cause loss of one or more partitions. 
Solution:
To correct the problem you will need to backup the partitions and then delete and recreate them and restore the data. You may need to use the same partitioning program that you used to create the partitions in order to delete them.   

Error_500 

Problem: This server has encountered an internal error which prevents it >from fulfilling your request. The most likely cause is a misconfiguration. Please ask the administrator to look for messages in the server's error log. 
Solution:
The web server provides this message whenever perl has a problem *of any nature*; i.e. syntax error, etc, anything. To debug the problem, you'll need to locate the web server's error_log (try looking for /usr/local/htdocs and browse around) and get the exact details from there.   

Error_691 

Problem: Access denied because username and/or password is invalid on the domain 
Solution:
Error 691 is caused by Dial-Up Networking (DUN) version conflicts created during the installation of some programs or incorrect user name and password on Dial-Up Network.  Please note: CS2000 and AOL5.0 do NOT use DUN.  You must be connected to the net by logging onto CS2000 or AOL5.0 then access Internet Explorer.   

Failed DNS lookup 

Problem: DNS stands for the Domain Name System, which is the system that looks up the name of a website, finds a corresponding number (similar to a phone number), then directs your request to the appropriate web server on the Internet. When the lookup fails, the host server can't be located.
Solution: Try hitting the Reload or Refresh button on your browser toolbar. If this doesn't work, check the address and enter it again. If all else fails, try again later. 

File contains no data 

Problem: The site has no web pages on it. 
Solution:
Check the address and enter it again. If you get the same error message, try again later. 

Helper application not found 

Problem: You're trying to load a file of a type that your browser doesn't recognize. Most browsers can be enabled to view or load file types that they don't otherwise recognize. These files can be sound files, movie clips, graphics, ZIP archive files, or any other type of file you are trying to download.
Solution: The dialog box that carries this message will tell you the file type that is missing. You can then follow your browser's instructions for assigning a viewer for each file format you wish to view online. It's often better to have certain file formats not assigned to helper applications for Internet browsers. When files are not assigned to helper applications, the dialog box you receive has a "Save to Disk" option. This can often be useful when you want to download files, such as ZIP archive files, to save them instead of extracting them right away 

Host unavailable 

Problem: The web server is down. 
Solution:
Try hitting the Reload or Refresh button. If this doesn't, try again later. 

Host unknown 

Problem: The web server is down, the site may have moved or you've been disconnected from the Net. 
Solution:
Try hitting the Reload or Refresh button and check to see that you are still online. If this fails, try using a search engine to find the site. It may have a new address.   

Installation "Error 117"   

Problem: A certain batch of CDs contained a strange glue-like substance on them that causes this error to popup because a track on the CD cannot be read. 
Solution:
Clean the CD using Windex or some equivalent cleaner to remove the offending substance.  The other possible cause of this error is a damaged or scratched CD, if cleaning the CD does not make the error cease then the customer should order a replacement CD.   

Network connection refused by the server 

Problem: The web server is busy. 
Solution:
Try again in a while.   

NNTP server error 

Problem: You're trying to log on to a Usenet newsgroup, but you can't get to it. The Usenet server is something that's made available by your Internet service provider, so it may be that this newsgroup isn't available at all. 
Solution:
Make sure you've typed the URL correctly. If that doesn't help, try again later. If the problem persists, contact your access provider and give them a piece of your mind.   

Permission denied 

Problem: You're trying to upload a file to an ftp site, and the site's administrator doesn't want you to. Alternatively, you're using the wrong syntax when trying to get a file. Or maybe the site is currently too busy to handle your upload. 
Solution: First check that you used the correct syntax. Then try again later. If the problem persists, send email to the Webmaster and ask how you can upload a file to that site.   

Too many connections--try again later 

Problem: This is another variation on the rush-hour error message. You've picked the wrong time to call, that's all. 
Solution:
Do as it says--try again later, or keep hitting the Refresh button until you succeed. 

Too many users 

Problem: No ftp site has unlimited access: physical connections or administrator policy allocate a number of anonymous users to a given site. When that number is exceeded, all who try to log on receive this message. 
Solution:
Just keep trying until you get lucky. However, on a busy site (like Netscape's the week after a big announcement) or one with very limited access rights, you may be out of luck. If so, check to see whether the site has mirrors, and try one of those.   

Unable to locate host 

Problem: The web server is down or you've been disconnected from the Net. 
Solution: Try hitting the Reload or Refresh button and check to see that you are still online. 

Unable to locate server 

Problem: The web server is out-of-business or you may have entered the address incorrectly.
Solution: Check the address and try typing it in again.   

Viewer not found 

Problem: Your browser doesn't recognize a file at the Web or Net site you're visiting. Viewable files aren't necessarily graphics--they can be sound files, movie clips, ZIP or SIT archive files, and so on. If it's not a GIF or JPEG file, your browser may not know what it is. 
Solution:
The dialog box that carries this message will usually give a clue about the file type that's missing. (You may see some gibberish about octet streams, but after that you'll probably see some reference to graphic-TIFF, which gives it away.) Look at CNET's Survival Kits for your computing platform (Mac, PC, or Unix) for viewers for the most common file types. Then follow your browser's instructions for assigning a viewer for each file format you wish to view online.   

You can't log on as an anonymous user 

Problem: This message covers a multitude of sins. Some ftp sites allow people who aren't members, some don't. Others may allow nonmembers, but limit the number of visitors. Another possibility is that your browser doesn't support anonymous ftp access. The way most browsers handle this is to submit "anonymous" as the user ID and your email address as the password. The America Online browser is one of the few that don't do this. 
Solution:
Either try again later after the rush hour or enter your user ID and password manually (using ftp software such as WS-FTP). Remember: your ID is anonymous and your password is your email address.   

Four Rules-of-Thumb for Dealing with Internet Problems 

  1. If you get a message saying the domain name server can't find your page and you're sure you've typed it in correctly or clicked on a valid link, try it again - TWO more times! (Sometimes packets don't get there!) 
  2. If you get a "Not found" message, the page may be temporarily missing because of miscoding at the target site. Try it again tomorrow...or try the home page for the site and send e-mail asking them to restore the page. 
  3. Be aware that sometimes a page you've visited recently may be coming from your cache (or the cache on a proxy server within your company). To get the "fresh" version of the page, click on "Reload" in your tool bar. 
  4. The Temporary Internet Files CACHE builds up QUICKLY. This results in slow page loading, and consequent timed-out connections. HISTORY files also build up with possible damaged or corrupt webpage files being stored.  These can cause lock-ups Internet Explorer and Netscape   Clear the CACHE and HISTORY frequently.