If all pages always show a 500 internal server error:
- Make sure you didn't upload to a /cgi-bin/ directory. WSN Links is PHP, not Perl, so it doesn't belong there.
- A problem in the .htaccess file can cause a 500 error. Check if the error goes away when deleting .htaccess. If so, work through it to find the line that's killing it (or ask for support).
- A bad chmod value can also cause a 500 error. Servers that don't allow 777 directories sometimes give these errors when using 777 -- try setting the directory to 755 instead (and be sure to change the Settings->System Settings value to 775 as well if that's the issue).
If all pages temporarily show a 500 internal server error:
- Your web host was probably experiencing difficulties for a bit.
If pages sometimes show a 500 internal server error:
- A few servers require a -f parameter in sending emails, though the vast majority should not use -f. Go to Admin Panel -> E-Mails -> E-Mail Preferences and set "Use -f parameter in sending mail?" to "yes". See if that clears up the error. If it doesn't, turn the -f off again.
- Other sorts of malformed mail may also cause a 500, such as a bad "to" address, though WSN automatically avoids sending emails to a blank recipient.
- A problem in the .htaccess file can cause a 500 error. Check if the error goes away when deleting .htaccess. If so, work through it to find the line that's killing it (or ask for support). As a temporary measure until solving the .htaccess problem, disable URL rewriting at Admin -> Settings -> SEO so that your site will be navigable.
- A bad chmod value can also cause a 500 error. Servers that don't allow 777 directories sometimes give these errors when using 777 -- try setting the directory to 755 instead, and the files in the base and admin directories to 644.
- If you're running PHP as CGI then 500 errors become much more common and can mean many more things. See http://encodable.com/internal_server_error/