diff --git a/appveyor.yml b/appveyor.yml
index 36246bb..7e43e65 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -64,7 +64,7 @@
     - cmd: set GAMEDATA_FOLDER=%APPVEYOR_BUILD_FOLDER%\GameData
     - cmd: set ASSEMBLY_FOLDER=%GAMEDATA_FOLDER%\CommNetConstellation\Plugins
     # download required KSP DLLs
-    - cmd: curl -fsS -o%DOWNLOAD_FOLDER%\dlls.7z https://d237kiopfuf7h0.cloudfront.net/download/KSPDLL_1_7_1.zip
+    - cmd: curl -fsS -o%DOWNLOAD_FOLDER%\dlls.7z https://d237kiopfuf7h0.cloudfront.net/download/KSPDLL_1_7_3.zip
     # extract them
     - cmd: cd %DOWNLOAD_FOLDER% & dir
     - cmd: 7z.exe e -p%DLL_ARCH_PASS% -o%ASSEMBLY_FOLDER% %DOWNLOAD_FOLDER%\dlls.7z
@@ -263,7 +263,7 @@
     - cmd: set GAMEDATA_FOLDER=%APPVEYOR_BUILD_FOLDER%\GameData
     - cmd: set ASSEMBLY_FOLDER=%GAMEDATA_FOLDER%\CommNetConstellation\Plugins
     # download required KSP DLLs
-    - cmd: curl -fsS -o%DOWNLOAD_FOLDER%\dlls.7z https://d237kiopfuf7h0.cloudfront.net/download/KSPDLL_1_7_1.zip
+    - cmd: curl -fsS -o%DOWNLOAD_FOLDER%\dlls.7z https://d237kiopfuf7h0.cloudfront.net/download/KSPDLL_1_7_3.zip
     # extract them
     - cmd: cd %DOWNLOAD_FOLDER% & dir
     - cmd: 7z.exe e -p%DLL_ARCH_PASS% -o%ASSEMBLY_FOLDER% %DOWNLOAD_FOLDER%\dlls.7z