Don't panic- It's fixable in 5 minutes.
Why this occured?
>This is a rare error that occurs with servers which
are not using the latest apache and php.ini compile which is compatible with Walmart API.
But--- Its SUPER SUPER SUPER easy to fix it.
You need to replace two files on WooCommerce
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Step 1 - Download This File
Unzip it.
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Step 2-
Now- Login to your hosting server via cPanel or via FTP.
Then go to folder called "wp-content" then "plugins" then "woocommerce" then
"templates" - Now we are ready to replace TWO files.
First file- short-description.php goes inside the folder called "single-product"
Second file- description.php goes inside the folder called "tabs"
Once these two files are updated- You are good to go.
**UPDATE: If you follow the above instructions and you are still having issues, try changing WordPress themes. "StoreFront" seems to be working well in the scenerio.
Here is a video that goes over what we just explained above.