diff --git a/main/ui/src/main/java/org/cryptomator/ui/logging/ConfigurableFileAppender.java b/main/ui/src/main/java/org/cryptomator/ui/logging/ConfigurableFileAppender.java
index 97deffe41..52a1c6732 100644
--- a/main/ui/src/main/java/org/cryptomator/ui/logging/ConfigurableFileAppender.java
+++ b/main/ui/src/main/java/org/cryptomator/ui/logging/ConfigurableFileAppender.java
@@ -2,11 +2,11 @@ package org.cryptomator.ui.logging;
 
 import java.io.IOException;
 import java.io.Serializable;
-import java.net.URI;
 import java.net.URISyntaxException;
 import java.nio.file.FileSystems;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.regex.Pattern;
 
 import org.apache.commons.lang3.SystemUtils;
 import org.apache.logging.log4j.core.Filter;
@@ -30,6 +30,7 @@ public class ConfigurableFileAppender extends AbstractOutputStreamAppender<FileM
 	private static final long serialVersionUID = -6548221568069606389L;
 	private static final int DEFAULT_BUFFER_SIZE = 8192;
 	private static final String DEFAULT_FILE_NAME = "cryptomator.log";
+	private static final Pattern DRIVE_LETTER_WITH_PRECEEDING_SLASH = Pattern.compile("^/[A-Z]:", Pattern.CASE_INSENSITIVE);
 
 	protected ConfigurableFileAppender(String name, Layout<? extends Serializable> layout, Filter filter, FileManager manager) {
 		super(name, layout, filter, true, true, manager);
@@ -66,8 +67,12 @@ public class ConfigurableFileAppender extends AbstractOutputStreamAppender<FileM
 		} else {
 			// relative Path:
 			try {
-				final URI jarFileLocation = ConfigurableFileAppender.class.getProtectionDomain().getCodeSource().getLocation().toURI();
-				final Path workingDir = FileSystems.getDefault().getPath(jarFileLocation.getPath()).getParent();
+				String jarFileLocation = ConfigurableFileAppender.class.getProtectionDomain().getCodeSource().getLocation().toURI().getPath();
+				if (SystemUtils.IS_OS_WINDOWS && DRIVE_LETTER_WITH_PRECEEDING_SLASH.matcher(jarFileLocation).find()) {
+					// on windows we need to remove a preceeding slash from "/C:/foo/bar":
+					jarFileLocation = jarFileLocation.substring(1);
+				}
+				final Path workingDir = FileSystems.getDefault().getPath(jarFileLocation).getParent();
 				filePath = workingDir.resolve(fileName);
 			} catch (URISyntaxException e) {
 				LOGGER.error("Unable to resolve working directory ", e);
diff --git a/main/ui/src/main/java/org/cryptomator/ui/util/SingleInstanceManager.java b/main/ui/src/main/java/org/cryptomator/ui/util/SingleInstanceManager.java
index a14b9f242..a8c3fd0c7 100644
--- a/main/ui/src/main/java/org/cryptomator/ui/util/SingleInstanceManager.java
+++ b/main/ui/src/main/java/org/cryptomator/ui/util/SingleInstanceManager.java
@@ -140,7 +140,7 @@ public class SingleInstanceManager {
 			if (key.isAcceptable()) {
 				final SocketChannel accepted = channel.accept();
 				if (accepted != null) {
-					LOG.info("accepted incoming connection");
+					LOG.debug("accepted incoming connection");
 					accepted.configureBlocking(false);
 					accepted.register(selector, SelectionKey.OP_READ | SelectionKey.OP_WRITE);
 				}
@@ -157,7 +157,7 @@ public class SingleInstanceManager {
 				if (!state.write.hasRemaining()) {
 					state.write = null;
 				}
-				LOG.debug("wrote welcome. switching to read only.");
+				LOG.trace("wrote welcome. switching to read only.");
 				key.interestOps(SelectionKey.OP_READ);
 			}
 
@@ -247,7 +247,7 @@ public class SingleInstanceManager {
 		try {
 			channel = SocketChannel.open();
 			channel.configureBlocking(false);
-			LOG.info("connecting to instance {}", port.get());
+			LOG.debug("connecting to instance {}", port.get());
 			channel.connect(new InetSocketAddress(InetAddress.getLoopbackAddress(), port.get()));
 
 			SocketChannel fChannel = channel;
@@ -255,7 +255,7 @@ public class SingleInstanceManager {
 				return Optional.empty();
 			}
 
-			LOG.info("connected to instance {}", port.get());
+			LOG.debug("connected to instance {}", port.get());
 
 			final byte[] bytes = applicationKey.getBytes();
 			ByteBuffer buf = ByteBuffer.allocate(bytes.length);
@@ -313,7 +313,7 @@ public class SingleInstanceManager {
 
 		final int port = ((InetSocketAddress) channel.getLocalAddress()).getPort();
 		Preferences.userNodeForPackage(Cryptomator.class).putInt(applicationKey, port);
-		LOG.info("InstanceManager bound to port {}", port);
+		LOG.debug("InstanceManager bound to port {}", port);
 
 		Selector selector = Selector.open();
 		channel.register(selector, SelectionKey.OP_ACCEPT);
diff --git a/main/ui/src/main/java/org/cryptomator/ui/util/mount/WindowsWebDavMounter.java b/main/ui/src/main/java/org/cryptomator/ui/util/mount/WindowsWebDavMounter.java
index b8bc246c0..eed6fae4f 100644
--- a/main/ui/src/main/java/org/cryptomator/ui/util/mount/WindowsWebDavMounter.java
+++ b/main/ui/src/main/java/org/cryptomator/ui/util/mount/WindowsWebDavMounter.java
@@ -32,7 +32,7 @@ import org.cryptomator.ui.util.command.Script;
 final class WindowsWebDavMounter implements WebDavMounterStrategy {
 
 	private static final Pattern WIN_MOUNT_DRIVELETTER_PATTERN = Pattern.compile("\\s*([A-Z]:)\\s*");
-	private static final int MAX_MOUNT_ATTEMPTS = 10;
+	private static final int MAX_MOUNT_ATTEMPTS = 12;
 
 	@Override
 	public boolean shouldWork() {
@@ -42,9 +42,11 @@ final class WindowsWebDavMounter implements WebDavMounterStrategy {
 	@Override
 	public void warmUp(int serverPort) {
 		try {
-			final Script proxyBypassCmd = fromLines("reg add \"HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\" /v \"ProxyOverride\" /d \"<local>;0--1.ipv6-literal.net\" /f");
+			final Script proxyBypassCmd = fromLines("reg add \"HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\" /v \"ProxyOverride\" /d \"<local>;0--1.ipv6-literal.net;0--1.ipv6-literal.net:%PORT%\" /f");
+			proxyBypassCmd.addEnv("PORT", String.valueOf(serverPort));
 			proxyBypassCmd.execute();
-			final Script mountCmd = fromLines("net use * http://0--1.ipv6-literal.net:" + serverPort + "/bill-gates-mom-uses-goto /persistent:no");
+			final Script mountCmd = fromLines("net use * http://0--1.ipv6-literal.net:%PORT%/bill-gates-mom-uses-goto /persistent:no");
+			mountCmd.addEnv("PORT", String.valueOf(serverPort));
 			mountCmd.execute();
 		} catch (CommandFailedException e) {
 			// will most certainly throw an exception, because this is a fake WebDav path. But now windows has some DNS things cached :)
@@ -53,13 +55,16 @@ final class WindowsWebDavMounter implements WebDavMounterStrategy {
 
 	@Override
 	public WebDavMount mount(URI uri, String name) throws CommandFailedException {
+		final Script proxyBypassCmd = fromLines("reg add \"HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\" /v \"ProxyOverride\" /d \"<local>;0--1.ipv6-literal.net;0--1.ipv6-literal.net:%PORT%\" /f");
+		proxyBypassCmd.addEnv("PORT", String.valueOf(uri.getPort()));
 		final Script mountScript = fromLines("net use * http://0--1.ipv6-literal.net:%PORT%%DAV_PATH% /persistent:no");
 		mountScript.addEnv("PORT", String.valueOf(uri.getPort())).addEnv("DAV_PATH", uri.getRawPath());
 		String driveLetter = null;
 		// The ugliness of the following 20 lines is solely windows' fault. Deal with it.
 		for (int i = 0; i < MAX_MOUNT_ATTEMPTS; i++) {
 			try {
-				final CommandResult mountResult = mountScript.execute(10, TimeUnit.SECONDS);
+				proxyBypassCmd.execute();
+				final CommandResult mountResult = mountScript.execute(5, TimeUnit.SECONDS);
 				driveLetter = getDriveLetter(mountResult.getStdOut());
 				break;
 			} catch (CommandFailedException ex) {
@@ -67,8 +72,8 @@ final class WindowsWebDavMounter implements WebDavMounterStrategy {
 					throw ex;
 				} else {
 					try {
-						// retry after 2s
-						Thread.sleep(2000);
+						// retry after 2.5s
+						Thread.sleep(2500);
 					} catch (InterruptedException e) {
 						Thread.currentThread().interrupt();
 					}