Index: src/main/java/hudson/plugins/cygpath/CygpathLauncherDecorator.java
===================================================================
--- src/main/java/hudson/plugins/cygpath/CygpathLauncherDecorator.java	(revision 150011)
+++ src/main/java/hudson/plugins/cygpath/CygpathLauncherDecorator.java	(revision 150012)
@@ -82,6 +82,11 @@
                     if (exe.indexOf('/')<0 && exe.indexOf('\\')<0)
                         return cmds;    // if the executable is a single token, it'll be found in PATH. "cygpath -w" would append the current directory in front, which won't work.
 
+						
+					if (getCygpathExe() == null) {
+						return cmds; // dont do the modifications in case that cygwin is not installed
+					}
+						
                     ByteArrayOutputStream out = new ByteArrayOutputStream();
                     if(base.launch().cmds(getCygpathExe(),"-w",exe).stdout(out).join()==0) {
                         // replace by the converted path
@@ -135,11 +140,19 @@
                 }
             }
 
-            throw new IOException2("Failed to locate Cygwin installation. Is Cygwin installed?",err);
+			// situation, where cygpath is not found or installed  - no error.
+			return null;
         }
 
         public String call() throws IOException {
-            return new File(getCygwinRoot(),"bin\\cygpath").getPath();
+			File root = getCygwinRoot();
+			if (root != null) {
+				return new File(root,"bin\\cygpath").getPath();
+			}
+			else {
+			         // cygwin not installed.
+				return null;
+			}
         }
     }
 }