M2E Pro is a native multi-channel solution for Magento platform. The Module allows easily integrating Magento Inventory to eBay/Amazon and managing your Channel sales.
M2E Pro Extension is improved on a constant basis to provide you with the highest level of service. The detailed information about each version released can be found in Release Notes section for Magento v1.x and Magento v2.x separately. It is strongly recommended to use the most up-to-date version.
Note: no data can be lost during an upgrade process. However, please, always back up your system prior to any upgrade related activity.
Depending on which version of Magento you are using, follow the appropriate instructions.
How to install/upgrade M2E Pro for Magento v1.x?
There are several methods you can use to install/upgrade M2E Pro Extension for Magento v1.x: