Problem

A Magento attribute dispplayed attribute (quite often custom attribute) may be displayed in red color in Attribute Mapping table (see screenshot above). This means that given such an attribute is not possible to export , because that out of the box as the attribute is not present in Product Flat Catalog. Or, alternatively,

Alternatively it means Flat Catalog as a whole is not enabled. 

Solution

In order to export any "red product attribute", follow these steps:

1. Double check that Flat Product Catalog and Flat Category Catalog is Run configuraion check to find out if all requirements for Koongo are met.
   • Alternatively, double check that Flat Product Catalog and Flat Category Catalog is enabled in System → Configuration → Catalog → Frontend.
2. Further, to allow export of any "red product attribute" follow these steps:
   
   1. Navigate to the attribute's detail in Catalog → Attributes → Manage attributes. Then, set the option Use in product listing to Yes and save attribute details.
   2. Finally, reindex Product Flat Index in System → Index management and refresh cache. Sometimes you have to do this step twice.

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