The screen is blank when I try to update the WURFL

[kamermans]

After following the instructions to install Tera-WURFL 2.x, I click on Update the database from local file and the screen goes blank.

This is happening because there is an error being generated that is not being properly handled from within Tera-WURFL and it is getting through to PHP. Your server is configured to suppress all errors and so it shows nothing as a result.

There are two things you can change to be able to see the errors. Tera-WURFL attempts to do it for you but sometimes they need to be set in the Apache config or a .htaccess file:

display_errors on
error_reporting E_ALL & ~E_NOTICE

http://www.php.net/manual/en/errorfunc.configuration.php#ini.error-log

The most common causes of errors at this step are:

1. Your wurfl.xml file, data directory or log file is not writable
2. Your database connection information is incorrect
3. You do not have the correct Database modules (MySQLi or Microsoft SQL Server Driver for PHP)

[kamermans]

I've run across a few people who have also had this problem when their server doesn't have enough memory to process the wurfl.xml. Some web hosts will say that you have 2GB of RAM or more, but if you look in the fine print you are limited to 64MB per process. This means that Tera-WURFL (Apache + PHP) can only use a total of 64MB to parse the WURFL. This is not nearly enough to process the entire WURFL, but luckily there are two workarounds:

1. You can install Tera-WURFL on a server that does not have this memory per-process limitation and copy the Tera-WURFL database to the new server - the limitation only keeps you from updating the database from the admin interface.
2. You can download the WURFL Customizer application which lets you choose which capabilities you need from the WURFL and export a much smaller WURFL containing only these capabilities. Then you can upload the smaller version and update your database with that file.