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Login to the Magento administration interface.
Once logged in, select System > Configuration from the main administration menu at the top of the page.
On the configuration interface has loaded click on Advanced > Advanced on the left hand side.
This interface shows a list of all the available Magento plugins. Search for the PayU_RedirectPaymentPage plugin, select Enable (1) and click on the Save Config (2) button
Enabling the payment gateway plugin: PayU Redirect Payment Page
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*** If the PayU option is not present, please clear the Magento Cache
The Payment Method Form configuration options for a PayU configuration are :
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Proceed to your store's front end and follow the purchase process on the frontend.