Lately we've seen some antivirus software reporting the iPayment .exe as a virus/threat, but there's no reason to worry, it's just a false positive.
The reason why some AV software might report it as a false positive is obfuscation. iPayment uses a small amount of obfuscation which sometimes results in a generic detection, but it is not a “real” detection.
The customer can safely add the .exe to their AV exception list and ignore the false positive.
If you decide to report this issue to support, please include log-files of the detection as well as the name of the AV software - this, in most cases, allows us to submit a 'false positive report' on the AV website.
If they review the .exe and determine that there is no issue, they will remove it from their threat list.