What can I do to improve the size of csv file that can successfully be imported via Feeds and Commerce Feeds I am using Feeds and Commerce Feeds to import product lists into my Drupal Commerce store.
I'm finding I have to keep the csv files really small for the import to succeed? As soon as the file is too big (the exact threshold size does not seem to be consistent) the system generates a 403 error as follows:

An AJAX HTTP error occurred. HTTP Result Code: 403 Debugging information follows. Path: /batch?id=260&amp;op=do StatusText: Forbidden ResponseText: Access denied


The file that resulted in this error was 577kB.

The only way around the problem is to have multiple csv files. These all have to be maintained and updated individually, which is very inefficient.

What can I do to improve this state of affairs?
The 403 HTTP code translates to access denied, which doesn't points to a problem in the size of the CSV file. Since it's using the batch API, which splits up the job in smaller chunks, it doesn't look like that it is the size of the file that is the problem. You should investigate the watchdog (dblog) and see if you can find the root cause.

This is the best answer I can provide with this limited information.