This will be fast, as I don't have a huge amount of time.

Create a separate file for the connection strings. You link it like so:

<connectionStrings configSource="db.config" />

You can then remove this file from your deployment before you push it out to
production and leave the db.config file for production out there. I will
have to check on connection strigns, but app settings can be set up like so:

<appSettings file="local.config">

<add key="communicationPort" value="1732"/>

</appSettings>

If the local.config file does not exist on your dev server, it will use the
keys from the block. You then set up the local.config out on the server for
the changes and it overrides any values from development.

I would also look up local.config, as it is somehow automagically removed
from deployment. We use that for app settings that change from local to
production.

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look at deployment projects. they support separate files for config
sections. as they build a dir for each deployment, you dev enviroment
can be debug, and production not.

-- bruce (sqlwork.com)