Zeffer - based on your posts, I respect the information sharing that you provide to others, but in this case I have to wonder why bother because you have not in fact provided any information that is useful.
Difficulty is relative, however you are partially correct. Installing the script is trivial, but getting it to work properly is obviously not, otherwise there wouldn't be as many posts to that affect in this forum.

Now, back to my problem which I could use some useful assisstance with:
Restatement of problem:
1. I get a 404 error when clicking on links to uploaded videos. I have confirmed that the .flv files exist and there were no apparent errors in the uploading process.
2. I get a 404 error when clicking on the "Watch" link.
3. When I sign in as a test user, and try to access the "My Profile" page (among others), I get a 404 error.

Environment:
1. I am running Ubuntu Linux 6.06 on a server I control and therefore have full administrative control.
2. To the best of my limited linux knowledge, I have installed and configured the vshare site requirements. Obviously not completely successfully or I wouldn't still be having a problem.

What have I done to troubelshoot?
1. I have followed the sugesstion of ADMIN and have verified that the .htaccess file is in the root directory of my vshare site. In my case, /var/www/vshare.
2. I have reviewed the files contents against the contents of the original supplied with the script and all seems to be in order.
3. To the best of my knowledge, Apache has been configured with .htaccess support (Here's where I am a little fuzzy). The relevant portion of my httpd.conf file is as follows:

LoadModule rewrite_module /usr/lib/apache2/modules/mod_rewrite.so
HostNameLookups off
ServerName 192.168.69.107:80
DocumentRoot /var/www
UseCanonicalName Off

<Directory /www/vshare>
AllowOverride All
Order allow,deny
Allow from all
</Directory>

4. I've also tried using Localhost and the sites domain name as arguments for the ServerName directive, to no avail.

When starting Apache, I get no errors and the Apache errors.log file shows no erros other than the 404's.

Is there something else that I can do to verify .htaccess has been enabled on the server correctly, because it seems that the file is not being processed correctly or not at all?

Is there a test I can run to see if the .htaccess file is being processed?

The Apache logs aren't helping me discover any problems, so is there another file that might contain relevant diagnostic info?

I've been to numerous Apache/Linux information websites looking for guidance on proper web server configuration including enabling .htaccess support and it seems like I've done what is required, but still I have the problem. I've run out of ideas where to go next with troubleshooting and need specific diagnostic advice.

Thanks in advance.