The screensaver on my TV shows this place; I would love to find where it is located!
Hallstätter See (a lake in Austria)
Source: Google Image Search
Hallstätter See or Lake Hallstatt is a lake in the Salzkammergut, Austria, located at 47°34′43″N 13°39′38″E. It is named after Hallstatt, a small market town in Austria, famous for its salt mining since prehistoric times and the starting point of the world's oldest and still working industrial pipeline – for brine to Bad Ischl (since 1596) and further to Ebensee.
I often see questions like this, and, while I do believe they are on-topic and related to travel, they are extremely easy to self answer.
Or if you have Google Chrome, right click on the image and click Search Google for image. This was kindly suggested by Andrew T below this answer.
If Google fails to find the answer then it's a good challenge.