401 - Authorization Required
403 - Forbidden
404 - DOMAIN.COM Page Not Found
500 - DOMAIN.COM Page Not Available
501 - Not Implemented
The Requested URL Was Not Found
Unable to Connect to www.domain.com
No Helper Application Defined

401 - Authorization Required

You may get the "401 - Authorization Required" error message when you try to view a
Web page with limited access. (A Web site may have a customized version of this error
message, such as a screen saying "Access Denied" or "Unavailable.")

If you don't think you should be getting this error:

Make sure that the Web address (or URL) that you typed in exactly matches the address
you were given. Check that the capitalization matches, that all words are spelled
properly, and that all the punctuation, like dots (.) and slashes (/), are correctly
placed. Remember, there are no spaces allowed in Web addresses. (A proper Web address
will look like http://www.domain.com or www.domain.com).

If you believe you should have access to the site, try sending e-mail to whomever
maintains the Web site. Their e-mail address is often on the main page of the Web site,
or you can try sending e-mail to the "Webmaster" of the site. If the Web address is
something like http://www.domain.com/, then the Webmaster's address will probably be
"webmaster@domain.com."

403 - Forbidden

This standard error message is generated by Web servers when you try to access a file that has not been correctly
configured by whomever maintains it. (The file needs to be set with "read permissions" for all users.) All that
probably means is that you can't view the page because whomever maintains the site set it up incorrectly.

This is a configuration issue that is beyond the control of the Internet service provider. Make sure the Web address you typed exactly matches
the Web address you were given. Spelling, punctuation, or capitalization errors can prevent the browser from finding
the page you're looking for. (Remember, there are no spaces allowed in Web addresses, and a proper Web address will
look like http://www.domain.com).

If you believe the Web address is correct, the problem may be with the Web server where the Web page "lives."
The server may be down for maintenance or too many people may be trying to access the server at once.

Wait a moment and click the Reload button (also called the Refresh button) to try again.

If you still can't reach the site, send e-mail to the Webmaster of that site with the exact error message you
are receiving.

404 - Page Not Found

A 404 - Not Found error means that there was no Web page with the name you specified at the Web site. This
could happen for a variety of reasons:

Make sure that the Web address (URL) that you typed in exactly matches the address you were given. Check that
the capitalization matches, that all words are spelled properly, and that all the punctuation, like dots (.)
and slashes (/), are correctly placed. Be sure you are using the forward slash (/) and not the backward slash
(\). (Remember, there are no spaces allowed in Web addresses, and a proper Web address will look like http://www.domain.com).

The page may have been renamed, moved, or deleted.

The person maintaining the Web page may no longer have an account at that location.
While not great news, the 404 - Not Found error tells you that that there is a Web site at that address, just not
the particular page you were looking for. You can usually poke around on the Web site to see if the page may have
been moved or renamed.

500 - Page Not Available

Web pages are stored on servers, machines that contain files and allow other servers (computers) to download files
from them. If the server has been incorrectly set up or is experiencing mechanical problems, it will return this error.

If you entered the URL manually, make sure it matches the URL exactly. Spelling, punctuation, and capitalization errors
can prevent you from seeing the page youre seeking.

If you continually receive this error message, you should wait and try again later until the problem has been resolved
by the server's administrators.

501 - Not Implemented

This error is a direct result of problems in the Web page's HTML (HyperText Markup Language). It usually occurs with Web pages that contain forms in which you type information and send it to a third party.

Try contacting the Webmaster at the site. If the Web address is something like http://www.domain.com/ then the Webmaster's address would be "webmaster@domain.com."

Unable to Connect to www.domain.com

When you receive the error message "Unable to Connect to <Web Address>," it means your Web browser cannot get to the Web site you want. There are a variety of reasons why this might happen. The Web address you typed may be incorrect. The Web site may have moved or may no longer exist. The Web server may be shut down or busy. Or there might even be network problems on the Internet.

Steps you can take include:

Make sure that the Web address (or URL) that you typed exactly matches the address you were given. Check that the capitalization matches, that all words are spelled properly, and that all the punctuation, like dots (.) and slashes (/), are correctly placed.

If you believe the URL is correct, the problem may be with the Web server. The server may be down, or too many people may be trying to access the server at once. Wait a moment and click the Reload button to try again.

Try connecting to other Web sites. If you can connect to other sites, the problem is probably with that one site so try again later. If you're having problems connecting to other sites though, you might be having a problem with your connection or your computer.


The Requested URL Was Not Found

This is a message that your Web browser will give you if it can't find a Web site to connect to at the address you specified. Depending on your Web browser, the message might read "Cannot open" or "Cannot retrieve" followed by the Web address.

Steps you can take include:

Use the Reload button to try to connect to the site again, or wait and try again later.

Clear your Web browser's disk cache. Depending on the browser, you will choose a menu item called "Preferences" or "Options." Look for an option for "Advanced" or "Browser" features, then press the button that says "Purge Cache," "Clear Cache," or "Empty Cache."

Try connecting to other Web sites. If you can connect to other sites, the problem is probably with that one site so try again later. If you're having problems connecting to other sites though, you might be having a problem with your connection or your computer

No Helper Application Defined

Helper applications are separate programs that deal with files that your Web browser isn't equipped to handle. For example, there are helper applications that decode and decompress file archives, play special sound formats, and show animated movies. The "No Helper Application Defined" error message means you have run into a file that requires a helper application, and you either don't have the helper application or your Web browser doesn't know where to find it.

In most Web browsers, you can select helper applications in the "Preferences" or "Options" menu item, where you should see an option to choose "Programs," "Helpers," or "Viewers." Each file type will have a description which includes the file extension (like .txt for text or .wav for a WAV sound file), a content type (called the MIME type, which is server information that tells the browser what kind of information it is, like "text/plain" or "audio/x-wav"), and then the location and name of the helper application used to process that file. You will be able to modify existing helper applications, add new ones, and remove old ones.

Below is a partial list of file extensions and MIME-types that are supported by the members.aol.com Web server. Again, the MIME-type tells the Web server how to send the file and tells the Web browser what kind of application to use to open the file. You can set up a helper application to view any of these files types with the Helper Application button. If a helper application has not been set up for one of these file types (or a file type not listed below), you will likely receive gibberish or an unreadable file that will be of no use to you.

.ai=application/postscript

.aif=audio/x-aiff

.aifc=audio/x-aiff

.aiff=audio/x-aiff

.art=image/x-art

.au=audio/basic

.avi=video/x-msvideo

.bin=application/octet-stream

.cdf=application/x-netcdf

.csh=application/x-csh

.dcr=application/x-director

.dir=application/x-director

.dvi=application/x-dvi

.dxr=application/x-director

.eps=application/postscript

.etx=text/x-setext

.exe=application/octet-stream

.fif=image/fif

.gif=image/gif

.gtar=application/x-gtar

.hdf=application/x-hdf

.hqx=application/mac-binhex40

.htm=text/html

.html=text/html

.ief=image/ief

.jpe=image/jpeg

.jpeg=image/jpeg

.jpg=image/jpeg

.js=application/x-javascript

.latex=application/x-latex

.ls=application/x-javascript

.man=application/x-troff-man

.me=application/x-troff-me

.mid=audio/x-midi

.mif=application/x-mif

.mocha=application/x-javascript

.mov=video/quicktime

.movie=video/x-sgi-movie

.mpe=video/mpeg

.mpeg=video/mpeg

.mpg=video/mpeg

.ms=application/x-troff-ms

.nc=application/x-netcdf

.oda=application/oda

.pbm=image/x-portable-bitmap

.pdf=application/pdf

.pgm=image/x-portable-graymap

.pnm=image/x-portable-anymap

.ppm=image/x-portable-pixmap

.ps=application/postscript

.qt=video/quicktime

.ra=audio/x-pn-realaudio

.ram=audio/x-pn-realaudio

.ras=image/x-cmu-raster

.rgb=image/x-rgb

.roff=application/x-troff

.rtf=application/rtf

.rtx=text/richtext

.sh=application/x-sh

.shar=application/x-shar

.snd=audio/basic

.spr=application/x-sprite

.sprite=application/x-sprite

.src=application/x-wais-source

.t=application/x-troff

.talk=text/x-speech

.tar=application/x-tar

.tcl=application/x-tcl

.tex=application/x-tex

.texi=application/x-texinfo

.texinfo=application/x-texinfo

.tif=image/tiff

.tiff=image/tiff

.tr=application/x-troff

.tsv=text/tab-separated-values

.txt=text/plain

.vmd=application/vocaltec-media-desc

.vmf=application/vocaltec-media-file

.vrml=x-world/x-vrml

.wav=audio/x-wav

.wrl=x-world/x-vrml

.xbm=image/x-xbitmap

.xpm=image/x-xpixmap

.xwd=image/x-xwindowdump

.zip=application/zip