diff --git a/Remote/Git.hs b/Remote/Git.hs
index 3f88a03343..7c75405431 100644
--- a/Remote/Git.hs
+++ b/Remote/Git.hs
@@ -425,7 +425,7 @@ rsyncOrCopyFile rsyncparams src dest p =
 			_ -> watchfilesize oldsz
 #endif
 	dorsync = rsyncHelper (Just p) $
-		rsyncparams ++ [Param src, Param dest]
+		rsyncparams ++ [File src, File dest]
 
 {- Generates rsync parameters that ssh to the remote and asks it
  - to either receive or send the key's content. -}
diff --git a/Remote/Rsync.hs b/Remote/Rsync.hs
index 768c15777b..f7abbbf2a6 100644
--- a/Remote/Rsync.hs
+++ b/Remote/Rsync.hs
@@ -242,7 +242,7 @@ rsyncRetrieve o k dest callback =
 		-- use inplace when retrieving to support resuming
 		[ Param "--inplace"
 		, Param u
-		, Param dest
+		, File dest
 		]
 
 rsyncRemote :: RsyncOpts -> (Maybe MeterUpdate) -> [CommandParam] -> Annex Bool
@@ -292,7 +292,7 @@ rsyncSend o callback k canrename src = withRsyncScratchDir $ \tmp -> do
 			[ Param "--recursive"
 			, partialParams
 			-- tmp/ to send contents of tmp dir
-			, Param $ addTrailingPathSeparator tmp
+			, File $ addTrailingPathSeparator tmp
 			, Param $ rsyncUrl o
 			]
 		else return False
diff --git a/Utility/Path.hs b/Utility/Path.hs
index 2c2fc35ff9..09cf739dc2 100644
--- a/Utility/Path.hs
+++ b/Utility/Path.hs
@@ -17,6 +17,11 @@ import Data.List
 import Data.Maybe
 import Control.Applicative
 
+#ifdef __WINDOWS__
+import Data.Char
+import System.FilePath.Posix as Posix
+#endif
+
 import Utility.Monad
 import Utility.UserInfo
 
@@ -185,3 +190,22 @@ dotfile file
 	| otherwise = "." `isPrefixOf` f || dotfile (takeDirectory file)
   where
 	f = takeFileName file
+
+{- Converts a DOS style path to a Cygwin style path. Only on Windows.
+ - Any trailing '\' is preserved as a trailing '/' -}
+toCygPath :: FilePath -> FilePath
+#ifndef __WINDOWS__
+toCygPath = id
+#else
+toCygPath p
+	| null drive = recombine parts
+	| otherwise = recombine $ "/cygdrive" : driveletter drive : parts
+  where
+  	(drive, p') = splitDrive p
+	parts = splitDirectories p'
+  	driveletter = map toLower . takeWhile (/= ':')
+	recombine = fixtrailing . Posix.joinPath
+  	fixtrailing s
+		| hasTrailingPathSeparator p = Posix.addTrailingPathSeparator s
+		| otherwise = s
+#endif
diff --git a/Utility/Rsync.hs b/Utility/Rsync.hs
index 652da8b20b..5f322a0cb7 100644
--- a/Utility/Rsync.hs
+++ b/Utility/Rsync.hs
@@ -1,6 +1,6 @@
 {- various rsync stuff
  -
- - Copyright 2010-2012 Joey Hess <joey@kitenet.net>
+ - Copyright 2010-2013 Joey Hess <joey@kitenet.net>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
@@ -49,7 +49,16 @@ rsyncUseDestinationPermissions :: CommandParam
 rsyncUseDestinationPermissions = Param "--chmod=ugo=rwX"
 
 rsync :: [CommandParam] -> IO Bool
-rsync = boolSystem "rsync"
+rsync = boolSystem "rsync" . rsyncParamsFixup
+
+{- On Windows, rsync is from Cygwin, and expects to get Cygwin formatted
+ - paths to files. (It thinks that C:foo refers to a host named "C").
+ - Fix up all Files in the Params appropriately. -}
+rsyncParamsFixup :: [CommandParam] -> [CommandParam]
+rsyncParamsFixup = map fixup
+  where
+  	fixup (File f) = File (toCygPath f)
+	fixup p = p
 
 {- Runs rsync, but intercepts its progress output and updates a meter.
  - The progress output is also output to stdout. 
@@ -65,7 +74,7 @@ rsyncProgress meterupdate params = do
 	reapZombies
 	return r
   where
-	p = proc "rsync" (toCommand params)
+	p = proc "rsync" (toCommand $ rsyncParamsFixup params)
 	feedprogress prev buf h = do
 		s <- hGetSomeString h 80
 		if null s