diff --git a/python/ycm/completers/cs/OmniSharpServer b/python/ycm/completers/cs/OmniSharpServer
index 53ea4d7f..c89ef98e 160000
--- a/python/ycm/completers/cs/OmniSharpServer
+++ b/python/ycm/completers/cs/OmniSharpServer
@@ -1 +1 @@
-Subproject commit 53ea4d7fb5190fa118ff36cdf1037644b4a2fc9f
+Subproject commit c89ef98ed9182bbca40ce47f2e6ccd1cca91036d
diff --git a/python/ycm/completers/cs/cs_completer.py b/python/ycm/completers/cs/cs_completer.py
index 8092e47a..6fe6644b 100755
--- a/python/ycm/completers/cs/cs_completer.py
+++ b/python/ycm/completers/cs/cs_completer.py
@@ -150,9 +150,12 @@ class CsharpCompleter( Completer ):
     command = ( omnisharp + ' -p ' + str( self._omnisharp_port ) + ' -s ' +
                 path_to_solutionfile )
 
-    if not utils.OnWindows():
+    if not utils.OnWindows() and not utils.OnCygwin():
       command = 'mono ' + command
 
+    if utils.OnCygwin():
+      command = command + ' --client-path-mode Cygwin'
+
     filename_format = os.path.join( utils.PathToTempDir(),
                                    'omnisharp_{port}_{sln}_{std}.log' )
 
diff --git a/python/ycm/utils.py b/python/ycm/utils.py
index c6b82ea9..d9128716 100644
--- a/python/ycm/utils.py
+++ b/python/ycm/utils.py
@@ -171,6 +171,10 @@ def OnWindows():
   return sys.platform == 'win32'
 
 
+def OnCygwin():
+  return sys.platform == 'cygwin'
+
+
 # From here: http://stackoverflow.com/a/8536476/1672783
 def TerminateProcess( pid ):
   if OnWindows():