Frequently Encountered Problems

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If you are experiencing any issue with HTML5 Builder, first read this list of Frequently Encountered Problems, which include most common issues and solutions or workarounds.


Could not determine My Documents path

You must have a My Documents folder in your user folder.

In Windows 7 and Windows 8, creating a folder with that name might not be enough. Go to Start, right-click Documents, go to Properties and, in the window that will pop up, click Restore Defaults at the bottom, and then click OK.

Help Resources

I cannot get the e-commerce sample to work

There is a readme.txt file along with the sample that explains how to install the components the application needs in order to work.


Sometimes components do not render right

This is a known error.

It sometimes happens with the first component rendered, sometimes with all the components, but it only happens when a component is rendered for the first time. “First time” as in “first time you open a file from the point of view of HTML5 Builder”. So, if you rename a project, all the files in it will suffer from this issue, since HTML5 Builder reads them as new files.

To workaround this issue, you only need to change a property in the components with visual consequences. For example, changing the size of a component will result in it being rendered again, and this time the component will render right.

I get JavaScript errors when working in the Designer, I cannot get any control to be rendered

This is a generic security issue with the web browser, that prevents HTML loading JavaScript from a different drive. There are workarounds, but you can verify if this is your problem by running it all from the same drive.


Fatal error: Class [class name] not found

Make sure all your pages have unique names for their Page or MPage container. Else, when serializing them into the session server-side, the information will get mixed up.

The web browser can't establish a connection to localhost:3572

Check the content of your C:\Windows\System32\drivers\etc\hosts file. The address should be linked to localhost.

Sometimes I get an Apache AV, I am using ajaxCall to call PHP functions

The Apache AV is caused by the URL “restore_session=1” parameter, which makes AJAX calls destroy the session, and PHP and Apache do not behave well with such an amount of destroys. It also makes the process slow.

To fix it:

  1. Remove the “restore_session” from your URL.
  2. Press Enter to reload the URL without the parameter.

I try to run a project and nothing happens

Make sure you have a default browser setup. If not, setup one from Home > Options.


Fatal error: Allowed memory size of [amount] bytes exhausted (tried to allocate [amount] bytes) in [filepath] on line [number]

You need to increase the memory available for PHP.

Edit your php.ini (the configuration file for your PHP installation) and set the memory_limit setting to a higher value. Its default value is usually 8M, so you can try with 32M. See PHP Settings if you are experiencing this problem with HTML5 Builder's internal server.

If your host does not allow you do change the PHP configuration file, you will need to call the ini_set() method instead. Add the following line at the beginning of the file: ini_set('memory_limit', '32M');. (you may replace '32M' with the value that better fits you)

For additional information on php.ini directives, check the PHP Manual.

Blank screen and no errors

If your web application runs fine when you run it from HTML5 Builder, but it does not work when you deploy it to your server and you get a blank screen instead, you should enable PHP error reporting to help find out what the problem is. Add the folowing lines at the beginning of your script:


The Input Filter PHP extension is not setup on this PHP installation, so the contents returned by Input is not filtered

That means you did not setup Input Filter PHP Extension in your system.

If you do not need to get input filter, you can edit your file, search for “throw new Exception” (around line 226), and safely remove that line.

Alternatively, you can setup the Input Filter extension.

If you are running PHP 5.2.x, then the PHP Input Filter is already built in, but the function filter_data was renamed to filter_var. An updated version of the class in that supports both PHP 5.1.x and PHP 5.2.x will be shipped soon.

  • If you have followed these instructions and are still getting the same error, please post about it in this forums topic.

Strict Standards: Declaration of [class]::[method] should be compatible with that of [another class]::[same method] in [filepath] on line [number]

You might get this message while working with a high PHP version with certain error flags enabled. This is because HTML5 Builder is making use of certain PHP features that your PHP version does not allow by default. To workaround the issue, place this line of code at the beginning of the problematic file:

error_reporting( E_ALL ^ E_NOTICE ^ E_STRICT );

That will make the problems go away, although the error messages might be still printed on the page. You can hide them using the following function:

ini_set('display_errors', '0');

Fatal error: Call to undefined function _() in [script]

The _() function is provided by the PHP Gettext module. Make sure you have that module enabled in the PHP configuration file (php.ini) in your web server.

See Also