fix appveyor builds

installers/common/WindowsInstaller.hs

@@ -85,7 +85,7 @@ signUninstaller opts = do
     -- in order to sign the uninstaller, we must first create a dummy nsis script that generates a stand-alone uninstaller at "install time"
     -- then "install" that dummy on the CI system, to create the uninstaller
     void $ proc "runtempinstaller.bat" [] mempty
-    signFile opts (tempDir </> "uninstall.exe")
+    signFile opts ("c:/uninstall.exe")
 
 signFile :: Options -> FilePath -> IO SigningResult
 signFile Options{..} filename = do
@@ -188,7 +188,7 @@ writeInstallerNSIS outName (Version fullVersion') installerConfig clusterName =
                     writeRegStr HKLM uninstallKey "QuietUninstallString" "\"$INSTDIR/uninstall.exe\" /S"
                     writeRegDWORD HKLM uninstallKey "NoModify" 1
                     writeRegDWORD HKLM uninstallKey "NoRepair" 1
-                file [] $ (str . encodeString $ tempDir </> "uninstall.exe")
+                file [] "c:/uninstall.exe"
 
         _ <- section "Start Menu Shortcuts" [] $ do
                 createDirectory "$SMPROGRAMS/$InstallDir"