Why was my selection of categories not properly saved ?
The Google Merchant Center module lets you decide which categories in your shop you wish to export to Google Shopping. In the "Export method" tab of the "Feed management" module section, tick the categories you want to export, and then save (on the bottom right) :
But, if you have a lot of categories (typically thousands of them), your selection may not get saved properly.
This is surely because of your server limit on the number of form fields that can be sent from the browser to the server in a POST request.
You will need to check with your web host to see how to increase some variables, usually defined at the PHP level in the php.ini file. The values you need to modify are :
For example :
If you have 2000 categories, all the post_max_size and max_input_vars will need to be at least 2200 (always add a safety margin of at least 10%).
Moreover, if you have the Suhosin PHP security extension installed, you will also need to change the values there:
Finally, sometimes, processing all these values can take a long time. So you may also need to increase the following value :
The standard value is 30 seconds, but you may need to increase that to 60 or more in some cases.