Export shipping + order stopped working suddenly

I did a backup restore of my files and since then the export shipping + order is not showing any option to download orders. It was working fine previously. Any clue or help would be appreciate.

Arunachala:

I did a backup restore of my files and since then the export shipping + order is not showing any option to download orders. It was working fine previously. Any clue or help would be appreciate.

More information about the above would be helpful in trying to suggest what the issue might be.

Backup restore === ?

Was that a backup of the files that was then immediately restored (like a test of the process?)
Was that a restore of some historical backup? (was a backup made before doing this?)
Does this backup restore have anything to do with the database or is it only related to the files that can be accessed say via ftp?

Export shipping + order === ???
Is this a specific plugin? Is it two different plugins? What guidance is provided about what it takes to display those/that option?

Almost most importantly why was this "backup restore" performed? Have you checked/double checked that the front end of the store is working correctly?

We updated wordpress to the latest version 4.9.1. The zen cart based store is a sub domain of the main site https://www.sriramanamaharshi.org . Many things ceased to work after the update and we found that the problem is solved if http is changed to https. We tried to restore to an older version to see if the problem will go away. We had a persistent problem in step 3 of 3 order confirmation where the confirm order button that takes the site to ccavenue payment gateway was not working. After much struggle we found that changing a line i configure.php from http to https solves the problems. The plugin that is no longer working is given by zen cart as https://www.zen-cart.com/downloads.php?do=file&id=406 It is not verfied for version 1.5.5e May be that is the problem. Hopefully the developer of the plugin will upgrade it.