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Adding EFK buttons to Polycom phones is fairly simple to do provided you are familiar with how to program EFK buttons and how to edit Polycom XML configuration files. A detailed PDF on creating EFK's can be found here. A common scenario for this is adding a Blind Transfer button while in a call. The first thing you have to do is ensure enhanced-feature-keys is checked under the Features section of the phone or group of phones in sipXconfig for which you wish to enable this feature.
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