Mobile payments are on their way to the Galaxy S6 and S6 Edge with Samsung Pay. But only on smartphones that are not rooted -- a process that allows Android smartphone owners to run apps, install tweaks and change settings that would otherwise be blocked by carriers, hardware manufacturers and Google.

Samsung Pay enables mobile payments on the Galaxy smartphones through near-field communication (NFC) for tap-to-pay transactions and magnetic secure transmission, which allows merchants to accept mobile payments without upgrading their existing equipment. But when customers attempt to use the service on a rooted device, an error message appears, according to SamMobile. “Access Denied,” the message reads. “Samsung Pay has been locked due to unauthorized modification. Call customer service.”

That means Samsung Galaxy owners will have to choose between rooting their device to modify it and keeping it stock to use Samsung’s mobile payment service.

The restriction was discovered during a limited trial of the service in South Korea. Samsung Pay was first announced in March and is expected to launch sometime this fall in the United States and South Korea, with an expansion to Europe and China at a later date.

Samsung Pay is but one of many mobile payment systems that have emerged in the past year. Apple launched its equivalent with Apple Pay on the iPhone 6 in September 2014 and Google is expected to roll out Android Pay later this year.

By the end of 2015, in-store mobile payments are projected to reach 22.6 million users, up 41.7 percent, with transactions valued at $8.95 billion, up from $3.5 billion in 2014, according to eMarketer.