How to change the value of attribute in appSettings section with Web.config transformation
You want something like: <appSettings> <add key=”developmentModeUserId” xdt:Transform=”Remove” xdt:Locator=”Match(key)”/> <add key=”developmentMode” value=”false” xdt:Transform=”SetAttributes” xdt:Locator=”Match(key)”/> </appSettings> See Also: Web.config Transformation Syntax for Web Application Project Deployment