Test on more versions of Visual Studio.
diff --git a/appveyor.yml b/appveyor.yml
index 620801a..1d9ea15 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -23,18 +23,38 @@
 # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+os: Visual Studio 2015
+
 environment:
   matrix:
-    - GENERATOR: "Visual Studio 12"
+    - GENERATOR: "Visual Studio 14 2015"
       BUILD_SHARED_LIBS: ON
 
-    - GENERATOR: "Visual Studio 12"
+    - GENERATOR: "Visual Studio 14 2015"
       BUILD_SHARED_LIBS: OFF
 
-    - GENERATOR: "Visual Studio 11"
+    - GENERATOR: "Visual Studio 12 2013"
       BUILD_SHARED_LIBS: ON
 
-    - GENERATOR: "Visual Studio 11"
+    - GENERATOR: "Visual Studio 12 2013"
+      BUILD_SHARED_LIBS: OFF
+
+    - GENERATOR: "Visual Studio 11 2012"
+      BUILD_SHARED_LIBS: ON
+
+    - GENERATOR: "Visual Studio 11 2012"
+      BUILD_SHARED_LIBS: OFF
+
+    - GENERATOR: "Visual Studio 10 2010"
+      BUILD_SHARED_LIBS: ON
+
+    - GENERATOR: "Visual Studio 10 2010"
+      BUILD_SHARED_LIBS: OFF
+
+    - GENERATOR: "Visual Studio 9 2008"
+      BUILD_SHARED_LIBS: ON
+
+    - GENERATOR: "Visual Studio 9 2008"
       BUILD_SHARED_LIBS: OFF
 
 platform: