Whenever you see this behavior, it is likely one of the following items.
- This means the AJAX cart module is not written to Magento standards. Its controller file is outputting using “echo” and then not exiting directly after output.
- To resolve, go to Extendware -> Manage Extensions -> Overview, click Third Party Extensions to the left and input “Cart” as the name.
- Look at the list and determine which Cart extension you are using.
- Note : If the “Identifier” column of the extensions is called "Company_Cart", then you would go the controller files in app/code/local/Company/Cart or app/code/community/Company/Cart and look in “controllers” directory.
- Open up the files and any functions that use “echo” add an exit to the end of the function and it will be resolved.