diff --git a/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoLibrary.java b/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoLibrary.java
index a90875cf917..04ea83d3248 100644
--- a/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoLibrary.java
+++ b/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoLibrary.java
@@ -206,7 +206,7 @@ public class ArduinoLibrary {
 				}
 			} else {
 				if (ArduinoBuildConfiguration.isSource(file.getName())) {
-					sources.add(file.getAbsolutePath());
+					sources.add(ArduinoBuildConfiguration.pathString(file.toPath()));
 				}
 			}
 		}
diff --git a/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoManager.java b/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoManager.java
index 2833ac7bd18..20a98296f0d 100644
--- a/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoManager.java
+++ b/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoManager.java
@@ -93,6 +93,7 @@ public class ArduinoManager {
 					.resolve(Paths.get(packageUrl.getPath()).getFileName());
 			File packageFile = packagePath.toFile();
 			if (download) {
+				Files.createDirectories(ArduinoPreferences.getArduinoHome());
 				Files.copy(packageUrl.openStream(), packagePath, StandardCopyOption.REPLACE_EXISTING);
 			}
 			if (packageFile.exists()) {
@@ -125,6 +126,7 @@ public class ArduinoManager {
 					.resolve(Paths.get(librariesUrl.getPath()).getFileName());
 			File librariesFile = librariesPath.toFile();
 			if (download) {
+				Files.createDirectories(ArduinoPreferences.getArduinoHome());
 				Files.copy(librariesUrl.openStream(), librariesPath, StandardCopyOption.REPLACE_EXISTING);
 			}
 			if (librariesFile.exists()) {
diff --git a/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoPlatform.java b/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoPlatform.java
index 9e3911ed537..8952d6b713a 100644
--- a/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoPlatform.java
+++ b/toolchains/arduino/org.eclipse.cdt.arduino.core/src/org/eclipse/cdt/arduino/core/internal/board/ArduinoPlatform.java
@@ -204,7 +204,7 @@ public class ArduinoPlatform {
 				}
 			} else {
 				if (ArduinoBuildConfiguration.isSource(file.getName())) {
-					sources.add(file.getAbsolutePath());
+					sources.add(ArduinoBuildConfiguration.pathString(file.toPath()));
 				}
 			}
 		}