PCLZIP_ERR_BAD_FORMAT (-10) error

There are a number of reasons why an auto update could fail with PCLZIP_ERR_BAD_FORMAT (-10) : Unable to find End of Central Dir Record signature error message. The most common ones, you need to pay attention to, are:

• cURL library is not available. It has to be installed and enabled on your server
• You are trying to upload other than .zip file type. Other format is not supported while uploading the theme or plugin in WordPress
• The .zip file is broken or incomplete
• There is not enough disc space on your host for WordPress to be able to unzip and upload the contents of the file
• An error might be thrown by a 3rd plugin or script on your site

If none of above is the reason, you should contact with your host as the problem is definitely on server side.