diff --git a/language-server/de.cau.cs.kieler.language.server/src/de/cau/cs/kieler/language/server/kicool/KiCoolLanguageServerExtension.xtend b/language-server/de.cau.cs.kieler.language.server/src/de/cau/cs/kieler/language/server/kicool/KiCoolLanguageServerExtension.xtend
index 459400415a..afc3820989 100644
--- a/language-server/de.cau.cs.kieler.language.server/src/de/cau/cs/kieler/language/server/kicool/KiCoolLanguageServerExtension.xtend
+++ b/language-server/de.cau.cs.kieler.language.server/src/de/cau/cs/kieler/language/server/kicool/KiCoolLanguageServerExtension.xtend
@@ -365,7 +365,7 @@ class KiCoolLanguageServerExtension implements ILanguageServerExtension, KiCoolC
      * @return model of specified resource
      */
     def Object getModelFromUri(String uri) {
-        val uriObject = URI.createURI(uri)
+        val uriObject = URI.createURI(URLDecoder.decode(uri, "UTF-8"))
         val ext = uriObject.fileExtension()
         if (!RegistrationLanguageServerExtension.registeredLanguageExtensions.contains(ext)) {
             val file = new File(uriObject.path)
diff --git a/language-server/de.cau.cs.kieler.language.server/src/de/cau/cs/kieler/language/server/simulation/SimulationLanguageServerExtension.xtend b/language-server/de.cau.cs.kieler.language.server/src/de/cau/cs/kieler/language/server/simulation/SimulationLanguageServerExtension.xtend
index 87b7cee0de..9b23912373 100644
--- a/language-server/de.cau.cs.kieler.language.server/src/de/cau/cs/kieler/language/server/simulation/SimulationLanguageServerExtension.xtend
+++ b/language-server/de.cau.cs.kieler.language.server/src/de/cau/cs/kieler/language/server/simulation/SimulationLanguageServerExtension.xtend
@@ -139,7 +139,7 @@ class SimulationLanguageServerExtension implements ILanguageServerExtension, Sim
      *  - simulationType should be one of Manual, Periodic, and Dynamic
      */
     override start(SimulationStartParam param) {
-        val decodedUri = URLDecoder.decode(param.uri, "UTF-8")
+        val decodedUri = param.uri
         while (listeners.contains(this)) {
             removeListener(this)
         }