I need to update something like 300 web.config files today, with the same change in each. I turned to my old friend Google for his recommendations and up popped a magnificent free tool from Nodesoft.
Why magnificent? It’s advanced mode allows you to specify start and end tags and update everything in between. That’s fantastic for dealing with big chunks of web.config files! Better yet, give it a file mask and a path and it will run through the entire folder tree if you like. Update whole servers in seconds.
I just wish I’d found it sooner…