Such a blank page is usually termed WSOD and d.o has a pretty exhaustive checklist for debugging it.
https://drupal.org/node/158043
From the checklist:
1) Enable Error Reporting by adding a snippet of code to your index.php 2) Check Apache (and PHP) Logs 3) Do not include the closing ?> on a PHP file. 4) Check for PHP4 Syntax Errors and Incompatibility 5) .. 6)..
The list is long. More @ https://drupal.org/node/158043
Cheers Tanay
On Sun, Jan 5, 2014 at 4:56 AM, Jamie Holly hovercrafter@earthlink.netwrote:
Blank screen is generally an error of some sorts. Check your server logs. A common cause is output being sent before headers. That can be caused by echoing something out before the headers are sent, or having a closing ?> at the end of a PHP file and something after it, even a blank line.
Jamie Holly http://hollyit.net
On 1/4/2014 5:54 PM, Roger wrote:
We have a most peculiar situation. While developing a theme in zen starterkit and following tuts and videos, etc the user login ceased to function. Cannot log in even with localhost/mydrupal/user which is how I normally login. All we get is a blank screen. Google suggested some overriding code to go into the page.tpl.php, which allowed login but returns the new theme screen but no admin even if we enter localhost/mydrupal/admin in the url. /user is core functionality, file template and css are all available, we have not changed any core files.
I used drush to make garland the default theme and tried to drush disable the zen theme but both fail. drush returns an error request -drush clear-cache drush which in turn returns the same error.
I did drush up to install drupal 7.25 and update modules but it did not help. Cannot find anything we have done in the dev theme which may relate to /user login or admin.
most perplexing. How would we solve the lack of admin and why would login cease to
function?
Help much appreciated Roger
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