I have red hat linux 7.2, apache 1.3.20, mysql 3.23.40, and
mod_auth_mysql 2.20.  I have the correct auth_mysql_info line in my
httpd.conf, and a correctly structured .htaccess file to reference and
look up the user/pass info in the database (trust me).  when I hit the
protected directory, the user/pass confirmation box pops up.  If I
enter incorrect data, it comes up again for confirmation.  But once I
get the correct values, it then gives me a Internal Server Error, with
nothing written to the error_log.  Arg! 

This is a re-opened question (I couldn't figure out how to re-open),
which was originally asked at
https://answers.google.com/answers/main?cmd=threadview&id=25104

To answer the request for clarification for the access log
63.228.80.194 - myke [15/Jun/2002:19:45:39 -0600] "GET /web-admin/
HTTP/1.1" 500 614 "-" "Mozilla/4.0 (compatible; MSIE 5.5; Windows 98;
PeoplePC 2.4.0; ISP)"

also, the error log being logged correctly, though that's a good point
to check. I swear nothing is being written to the error_log, and I am
checking the correct one.

Here is the .htaccess file:
AuthName "web site administration"
AuthType Basic
AuthUserFile /dev/null
AuthGroupFile /dev/null

<Limit GET>
        Auth_MySQL On
        Auth_MySQL_Authoritative On
        Auth_MySQL_DB climbing
        Auth_MySQL_Password_Table sites
        Auth_MySQL_Encrypted_Passwords off
        Auth_MySQL_Encryption_Types Plaintext
        Auth_MySQL_Username_Field username
        Auth_MySQL_Password_Field password
        Auth_MySQL_Empty_Passwords      On
        require valid-user
</Limit>

finally, the reason I'm re-opening it is that I found that if you add
"Satisfy Any".... it doesn't do ANY password checking at all!

the actual URL is 
http://www.climbingboulder.com/web-admin/
and the username/password that will work is myke/google.

Did you check the mysql logs? Also you may want to look into running
strace on your current apache process and tracing down whats going on.
Doesn't sound like to big of a problem to solve to me. If you would
like some more help let me know.

I don't think the MySQL logs will tell anything.
I couldn't find anyone with the same problem on a web search.

If climbingboulder-ga has C programming experience, I would suggest
recompiling Apache to statically include the mod_auth_mysql and put in
debugging information. Offhand I don't know what would cause the
Internal Server Error though - my experience with that is limited to
CGI scripts gone bad.

Thanks for the comments.

1) Where are the mysql logs?  I couldn't find them in /var/log, or
even within the mysql root directory.  perhaps I'm missing something.

2) mod_auth_mysql was compiled at run-time.

httpd -l
Compiled-in modules:
  http_core.c
  mod_env.c
  mod_log_config.c
  mod_mime.c
  mod_negotiation.c
  mod_status.c
  mod_include.c
  mod_autoindex.c
  mod_dir.c
  mod_cgi.c
  mod_asis.c
  mod_imap.c
  mod_actions.c
  mod_userdir.c
  mod_alias.c
  mod_access.c
  mod_auth.c
  mod_so.c
  mod_setenvif.c
  mod_ssl.c
  mod_auth_mysql.c
suexec: disabled; invalid wrapper /home/httpd/bin/suexec

Finally, I can find a number of people on the web with this same
error:
http://www.phpbuilder.com/forum/read.php3?num=3&id=105106&loc=0&thread=105106

http://groups.google.com/groups?q=mod_auth_mysql+internal+server+error&hl=en&lr=&ie=UTF8&oe=UTF8&safe=off&selm=slrn7nsbof.i1.juergen.leising%40jl2.hnet.de&rnum=1

http://groups.google.com/groups?hl=en&lr=&ie=UTF8&oe=UTF8&safe=off&selm=7ie3ek%24mvs%241%40nnrp1.deja.com

among others.... note the first one I posted what I thought was a
solution, but then I realized that "Satisfy Any" allows anyone in.

My MySQL logs are in /var/log/mysqld.log for the RPM version.

I was looking around for the MySQL distribution, and there turns to be
another one which in the freshmeat description, "the non-sucky one":

http://freshmeat.net/projects/mod_auth_mysql/

Which points to the Sourceforce project page:

http://sourceforge.net/projects/mod-auth-mysql/

Maybe this would have a better chance of working?

Does it work in IE? The reason I ask is that there is something
blinking in the back of my feable mind that tells me it's a glitch in
Netscape/Mozilla. I can't remember where I read it, and it didn't turn
up on the first search I ran.

If it works in IE, let me know that we're on the right track and I'll
try a bit harder to find the thread I was reading which described this
problem.

WebStock

Problem exists with:
  IE 6.0
  Mozilla 1.0
  Opera 6.01
  Netscape 4.0

:-(

Ah Ha! I solved it!

it appears that mod_auth_mysql does not know how to handle the
situation where, for a given username in a username/password combo, if
there is TWO records that contain that name.  It makes sense.  thus, a
table with

username | password
--------------------
myke     | password1
myke     | password2
joe      | password3

will produce an error with user myke, but it WILL work correctly for
user joe.

Took me a while to figure this one out, but that's the problem, and
the solution!