Join resulting in blank page or HTTP 500 error

Hello,

when I join the result page goes blank in Chrome and in IE I get a "HTTP 500 Internal Server Error"

When I create an event in Chrome the result page also goes blank.

The Join and add the event is still executed.

Any suggestions on what can have gone wrong?

Check the .htaccess file in the root of your Dolphin site.

Could it be due to caching settings in htaccess which were meant to speed site up?

## EXPIRES CACHING ##
<IfModule mod_expires.c>
ExpiresActive On
ExpiresByType image/jpg "access 1 week"
ExpiresByType image/jpeg "access 1 week"
ExpiresByType image/gif "access 1 week"
ExpiresByType image/png "access 1 week"
ExpiresByType text/css "access 1 week"
ExpiresByType text/html "access 1 week"
ExpiresByType application/pdf "access 1 week"
ExpiresByType text/x-javascript "access 1 week"
ExpiresByType application/x-shockwave-flash "access 1 week"
ExpiresByType image/x-icon "access 1 week"
ExpiresDefault "access 1 week"
</IfModule>
## EXPIRES CACHING ##

# BEGIN Cache-Control Headers
<ifModule mod_headers.c>
Header set Connection keep-alive
  <filesMatch "\.(ico|jpe?g|png|gif|swf)$">
    Header set Cache-Control "max-age=2592000, public"
  </filesMatch>
  <filesMatch "\.(css)$">
    Header set Cache-Control "max-age=604800, public"
  </filesMatch>
  <filesMatch "\.(js)$">
    Header set Cache-Control "max-age=216000, private"
  </filesMatch>
  <filesMatch "\.(x?html?|php)$">
    Header set Cache-Control "max-age=600, private, must-revalidate"
  </filesMatch>
</ifModule>
# END Cache-Control Headers

<ifModule mod_headers.c>
  <filesMatch "\\.(ico|pdf|flv|jpg|jpeg|png|gif|swf)$">
    Header set Cache-Control "max-age=2592000, public"
  </filesMatch>
  <filesMatch "\\.(css)$">
    Header set Cache-Control "max-age=604800, public"
  </filesMatch>
  <filesMatch "\\.(js)$">
    Header set Cache-Control "max-age=216000, private"
  </filesMatch>
  <filesMatch "\\.(xml|txt)$">
    Header set Cache-Control "max-age=216000, public, must-revalidate"
  </filesMatch>
  <filesMatch "\\.(html|htm|php)$">
    Header set Cache-Control "max-age=1, private, must-revalidate"
  </filesMatch>
</ifModule>

Bad .htaccess entries can cause a 500 error; so yes, if you added some to the .htaccess file, you could have caused the 500 error.  Replace the modified .htaccess file with the one that ships from Dolphin; if you have added entries for third party modules, you will need to add them to the .htaccess file that you import from the Dolphin zip.  If the 500 error disappears, then you know there is something in your modified .htaccess file that is causing the 500 error.