By default the deployment targets (Microsoft.Web.Publishing.targets) used when building a deployment package for a web app will automatically generate entries for connection strings. The problem is that it chooses really awful tag names for the parameters - for example:
This gave me a problem as the configuration system we use at Landmark to deploy our web apps can't have any spaces in its parameter tags. Fortunately, there's a quick solution.
It's easy enough to add a Parameters.xml file to your project to provide custom parameters - and in that file it's trivial to include a duplicate connection string parameter definition (that doesn't have spaces in the name).
The final part of the puzzle is to prevent the deployment targets from creating the default connection string entries on build. This is achieved by passing in the following (memorably-named) MSBuild parameter:
/parameter:AutoParameterizationWebConfigConnectionStrings=FalseThe deployment targets no longer add the connection string parameters by default, so you have to do so explicitly in your Parameters.xml file - but now YOU control the parameter name. Done.