diff --git a/runelite-client/src/main/java/net/runelite/client/config/ConfigManager.java b/runelite-client/src/main/java/net/runelite/client/config/ConfigManager.java
index 68989ea4d8..400083b815 100644
--- a/runelite-client/src/main/java/net/runelite/client/config/ConfigManager.java
+++ b/runelite-client/src/main/java/net/runelite/client/config/ConfigManager.java
@@ -36,9 +36,13 @@ import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import java.lang.reflect.Proxy;
+import java.nio.channels.FileLock;
+import java.nio.charset.Charset;
 import java.time.Instant;
 import java.util.Arrays;
 import java.util.Comparator;
@@ -179,7 +183,7 @@ public class ConfigManager
 
 		try (FileInputStream in = new FileInputStream(propertiesFile))
 		{
-			properties.load(in);
+			properties.load(new InputStreamReader(in, Charset.forName("UTF-8")));
 		}
 		catch (FileNotFoundException ex)
 		{
@@ -199,6 +203,7 @@ public class ConfigManager
 				if (split.length != 2)
 				{
 					log.debug("Properties key malformed!: {}", groupAndKey);
+					properties.remove(groupAndKey);
 					return;
 				}
 
@@ -225,7 +230,16 @@ public class ConfigManager
 
 		try (FileOutputStream out = new FileOutputStream(propertiesFile))
 		{
-			properties.store(out, "RuneLite configuration");
+			final FileLock lock = out.getChannel().lock();
+
+			try
+			{
+				properties.store(new OutputStreamWriter(out, Charset.forName("UTF-8")), "RuneLite configuration");
+			}
+			finally
+			{
+				lock.release();
+			}
 		}
 	}