diff --git a/src/main/scala/li/cil/oc/server/component/FileSystem.scala b/src/main/scala/li/cil/oc/server/component/FileSystem.scala
index 9f470449a..b93ea5d54 100644
--- a/src/main/scala/li/cil/oc/server/component/FileSystem.scala
+++ b/src/main/scala/li/cil/oc/server/component/FileSystem.scala
@@ -301,7 +301,7 @@ class FileSystem(val fileSystem: IFileSystem, var label: Label, val host: Option
 
   private def clean(path: String) = {
     val result = com.google.common.io.Files.simplifyPath(path)
-    if (result.startsWith("../")) throw new FileNotFoundException()
+    if (result.startsWith("../")) throw new FileNotFoundException(path)
     if (result == "/" || result == ".") ""
     else result
   }
diff --git a/src/main/scala/li/cil/oc/server/fs/CompositeReadOnlyFileSystem.scala b/src/main/scala/li/cil/oc/server/fs/CompositeReadOnlyFileSystem.scala
index 096615ce7..ec717ebb2 100644
--- a/src/main/scala/li/cil/oc/server/fs/CompositeReadOnlyFileSystem.scala
+++ b/src/main/scala/li/cil/oc/server/fs/CompositeReadOnlyFileSystem.scala
@@ -72,7 +72,7 @@ class CompositeReadOnlyFileSystem(factories: mutable.LinkedHashMap[String, Calla
 
   override def open(path: String, mode: Mode) = findFileSystem(path) match {
     case Some(fs) => fs.open(path, mode)
-    case _ => throw new FileNotFoundException()
+    case _ => throw new FileNotFoundException(path)
   }
 
   override def getHandle(handle: Int) = parts.valuesIterator.map(_.getHandle(handle)).find(_ != null).orNull
diff --git a/src/main/scala/li/cil/oc/server/fs/FileInputStreamFileSystem.scala b/src/main/scala/li/cil/oc/server/fs/FileInputStreamFileSystem.scala
index a405bb967..aae9728ac 100644
--- a/src/main/scala/li/cil/oc/server/fs/FileInputStreamFileSystem.scala
+++ b/src/main/scala/li/cil/oc/server/fs/FileInputStreamFileSystem.scala
@@ -38,7 +38,7 @@ trait FileInputStreamFileSystem extends InputStreamFileSystem {
     case file if file.exists() && file.isFile => Array(file.getName)
     case directory if directory.exists() && directory.isDirectory && directory.list() != null =>
       directory.listFiles().map(file => if (file.isDirectory) file.getName + "/" else file.getName)
-    case _ => throw new io.FileNotFoundException("no such file or directory")
+    case _ => throw new io.FileNotFoundException("No such file or directory: " + path)
   }
 
   // ----------------------------------------------------------------------- //
diff --git a/src/main/scala/li/cil/oc/server/fs/InputStreamFileSystem.scala b/src/main/scala/li/cil/oc/server/fs/InputStreamFileSystem.scala
index 82125ee33..cd61f41ba 100644
--- a/src/main/scala/li/cil/oc/server/fs/InputStreamFileSystem.scala
+++ b/src/main/scala/li/cil/oc/server/fs/InputStreamFileSystem.scala
@@ -36,9 +36,9 @@ trait InputStreamFileSystem extends api.fs.FileSystem {
       case Some(channel) =>
         handles += handle -> new Handle(this, handle, path, channel)
         handle
-      case _ => throw new FileNotFoundException()
+      case _ => throw new FileNotFoundException(path)
     }
-  } else throw new FileNotFoundException())
+  } else throw new FileNotFoundException(path))
 
   override def getHandle(handle: Int): api.fs.Handle = this.synchronized(handles.get(handle).orNull)
 
diff --git a/src/main/scala/li/cil/oc/server/fs/OutputStreamFileSystem.scala b/src/main/scala/li/cil/oc/server/fs/OutputStreamFileSystem.scala
index d6de4d06c..e53c99063 100644
--- a/src/main/scala/li/cil/oc/server/fs/OutputStreamFileSystem.scala
+++ b/src/main/scala/li/cil/oc/server/fs/OutputStreamFileSystem.scala
@@ -28,9 +28,9 @@ trait OutputStreamFileSystem extends InputStreamFileSystem {
         case Some(fileHandle) =>
           handles += handle -> fileHandle
           handle
-        case _ => throw new FileNotFoundException()
+        case _ => throw new FileNotFoundException(path)
       }
-    } else throw new FileNotFoundException()
+    } else throw new FileNotFoundException(path)
   })
 
   override def getHandle(handle: Int): api.fs.Handle = this.synchronized(Option(super.getHandle(handle)).orElse(handles.get(handle)).orNull)
diff --git a/src/main/scala/li/cil/oc/server/fs/ReadOnlyWrapper.scala b/src/main/scala/li/cil/oc/server/fs/ReadOnlyWrapper.scala
index 8b8be08c5..f5f7783c4 100644
--- a/src/main/scala/li/cil/oc/server/fs/ReadOnlyWrapper.scala
+++ b/src/main/scala/li/cil/oc/server/fs/ReadOnlyWrapper.scala
@@ -33,8 +33,8 @@ private class ReadOnlyWrapper(val fileSystem: api.fs.FileSystem) extends api.fs.
 
   override def open(path: String, mode: Mode) = mode match {
     case Mode.Read => fileSystem.open(path, mode)
-    case Mode.Write => throw new FileNotFoundException()
-    case Mode.Append => throw new FileNotFoundException()
+    case Mode.Write => throw new FileNotFoundException("Read-only filesystem; cannot open for writing: " + path)
+    case Mode.Append => throw new FileNotFoundException("Read-only filesystem; cannot open for appending: " + path)
   }
 
   override def getHandle(handle: Int) = fileSystem.getHandle(handle)
diff --git a/src/main/scala/li/cil/oc/server/fs/VirtualFileSystem.scala b/src/main/scala/li/cil/oc/server/fs/VirtualFileSystem.scala
index 21deb7fa0..7319faee5 100644
--- a/src/main/scala/li/cil/oc/server/fs/VirtualFileSystem.scala
+++ b/src/main/scala/li/cil/oc/server/fs/VirtualFileSystem.scala
@@ -67,7 +67,7 @@ trait VirtualFileSystem extends OutputStreamFileSystem {
   }
 
   override def rename(from: String, to: String) =
-    if (from == "" || !exists(from)) throw new FileNotFoundException()
+    if (from == "" || !exists(from)) throw new FileNotFoundException(from)
     else if (!exists(to)) {
       val segmentsTo = segments(to)
       root.get(segmentsTo.dropRight(1)) match {