diff --git a/platform/core-api/src/com/intellij/openapi/vfs/VfsUtilCore.java b/platform/core-api/src/com/intellij/openapi/vfs/VfsUtilCore.java
index d594b7d993fb..539e1f27c2e0 100644
--- a/platform/core-api/src/com/intellij/openapi/vfs/VfsUtilCore.java
+++ b/platform/core-api/src/com/intellij/openapi/vfs/VfsUtilCore.java
@@ -387,7 +387,7 @@ public class VfsUtilCore {
       String suffix = url.substring(index + 2);
 
       if (SystemInfoRt.isWindows) {
-        return prefix + "://" + suffix;
+        return prefix + URLUtil.SCHEME_SEPARATOR + suffix;
       }
       else if (removeLocalhostPrefix && prefix.equals(StandardFileSystems.FILE_PROTOCOL) && suffix.startsWith(LOCALHOST_URI_PATH_PREFIX)) {
         // sometimes (e.g. in Google Chrome for Mac) local file url is prefixed with 'localhost' so we need to remove it
diff --git a/platform/platform-impl/src/com/intellij/util/UrlImpl.java b/platform/platform-impl/src/com/intellij/util/UrlImpl.java
index ec2d7e02af60..04af1fada4e9 100644
--- a/platform/platform-impl/src/com/intellij/util/UrlImpl.java
+++ b/platform/platform-impl/src/com/intellij/util/UrlImpl.java
@@ -84,10 +84,17 @@ public final class UrlImpl implements Url {
   public String toDecodedForm() {
     StringBuilder builder = new StringBuilder();
     if (scheme != null) {
-      builder.append(scheme).append(URLUtil.SCHEME_SEPARATOR);
-    }
-    if (authority != null) {
-      builder.append(authority);
+      builder.append(scheme);
+      if (authority != null || isInLocalFileSystem()) {
+        builder.append(URLUtil.SCHEME_SEPARATOR);
+      }
+      else {
+        builder.append(':');
+      }
+
+      if (authority != null) {
+        builder.append(authority);
+      }
     }
     builder.append(getPath());
     if (parameters != null) {
@@ -104,7 +111,8 @@ public final class UrlImpl implements Url {
     }
 
     // relative path - special url, encoding is not required
-    if (path.charAt(0) != '/' && !isInLocalFileSystem()) {
+    // authority is null in case of URI or file URL
+    if ((path.charAt(0) != '/' || authority == null) && !isInLocalFileSystem()) {
       return toDecodedForm();
     }
 
diff --git a/platform/platform-impl/src/com/intellij/util/Urls.java b/platform/platform-impl/src/com/intellij/util/Urls.java
index a06247a56456..240c30686ef6 100644
--- a/platform/platform-impl/src/com/intellij/util/Urls.java
+++ b/platform/platform-impl/src/com/intellij/util/Urls.java
@@ -35,7 +35,7 @@ public final class Urls {
   private static final Logger LOG = Logger.getInstance(Urls.class);
 
   // about ";" see WEB-100359
-  private static final Pattern URI_PATTERN = Pattern.compile("^([^:/?#]+)://([^/?#]*)([^?#;]*)(.*)");
+  private static final Pattern URI_PATTERN = Pattern.compile("^([^:/?#]+):(//)?([^/?#]*)([^?#;]*)(.*)");
 
   @NotNull
   public static Url newUri(@NotNull String scheme, @NotNull String path) {
@@ -44,7 +44,7 @@ public final class Urls {
 
   @NotNull
   public static Url newFromEncoded(@NotNull String url) {
-    Url result = parse(url, true);
+    Url result = parse(url, false);
     LOG.assertTrue(result != null, url);
     return result;
   }
@@ -112,19 +112,18 @@ public final class Urls {
       scheme = "jar:" + scheme;
     }
 
-    String authority = StringUtil.nullize(matcher.group(2));
+    String authority = StringUtil.nullize(matcher.group(3));
 
-    String path = StringUtil.nullize(matcher.group(3));
+    String path = StringUtil.nullize(matcher.group(4));
     if (path != null) {
       path = FileUtil.toCanonicalUriPath(path);
     }
 
-    String parameters = matcher.group(4);
-    if (authority != null && StandardFileSystems.FILE_PROTOCOL.equals(scheme)) {
+    if (authority != null && (StandardFileSystems.FILE_PROTOCOL.equals(scheme) || StringUtil.isEmpty(matcher.group(2)))) {
       path = path == null ? authority : (authority + path);
       authority = null;
     }
-    return new UrlImpl(scheme, authority, path, parameters);
+    return new UrlImpl(scheme, authority, path, matcher.group(5));
   }
 
   // must not be used in NodeJS