diff --git a/Cargo.lock b/Cargo.lock
index d2f69483..06ebeb81 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -865,6 +865,16 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "42703706b716c37f96a77aea830392ad231f44c9e9a67872fa5548707e11b11c"
 
+[[package]]
+name = "fslock"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "04412b8935272e3a9bae6f48c7bfff74c2911f60525404edfdd28e49884c3bfb"
+dependencies = [
+ "libc",
+ "winapi 0.3.9",
+]
+
 [[package]]
 name = "futures-channel"
 version = "0.3.31"
@@ -2186,6 +2196,7 @@ dependencies = [
  "async-std",
  "bitflags 2.6.0",
  "derivative",
+ "fslock",
  "glob",
  "lazy_static",
  "log",
diff --git a/Cargo.toml b/Cargo.toml
index 5cd5d962..1442e151 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -78,6 +78,7 @@ filelocksmith = "0.1"
 image = { version = "0.25", default-features = false, features = ["gif", "jpeg", "png"] }
 fs_extra = "1.3"
 memmap2 = "0.9"
+fslock = "0.2"
 
 # default to small, optimized workspace release binaries
 [profile.release]
diff --git a/src/bins/src/commands/install.rs b/src/bins/src/commands/install.rs
index 2d6d2902..3fa45174 100644
--- a/src/bins/src/commands/install.rs
+++ b/src/bins/src/commands/install.rs
@@ -21,6 +21,7 @@ pub fn install(pkg: &mut BundleZip, install_to: Option<&PathBuf>, start_args: Op
     info!("Reading package manifest...");
     let app = pkg.read_manifest()?;
 
+
     info!("Package manifest loaded successfully.");
     info!("    Package ID: {}", &app.id);
     info!("    Package Version: {}", &app.version);
@@ -30,8 +31,6 @@ pub fn install(pkg: &mut BundleZip, install_to: Option<&PathBuf>, start_args: Op
     info!("    Package Machine Architecture: {}", &app.machine_architecture);
     info!("    Package Runtime Dependencies: {}", &app.runtime_dependencies);
 
-    let _mutex = shared::retry_io(|| windows::create_global_mutex(&app.id))?;
-
     if !windows::prerequisite::prompt_and_install_all_missing(&app, None)? {
         info!("Cancelling setup. Pre-requisites not installed.");
         return Ok(());
@@ -114,6 +113,11 @@ pub fn install(pkg: &mut BundleZip, install_to: Option<&PathBuf>, start_args: Op
 
     info!("Preparing and cleaning installation directory...");
     remove_dir_all::ensure_empty_dir(&root_path)?;
+    
+    info!("Acquiring lock...");
+    let paths = create_config_from_root_dir(&root_path);
+    let locator = VelopackLocator::new(paths, app);
+    let _mutex = locator.try_get_exclusive_lock()?;
 
     let tx = if dialogs::get_silent() {
         info!("Will not show splash because silent mode is on.");
@@ -122,10 +126,10 @@ pub fn install(pkg: &mut BundleZip, install_to: Option<&PathBuf>, start_args: Op
     } else {
         info!("Reading splash image...");
         let splash_bytes = pkg.get_splash_bytes();
-        windows::splash::show_splash_dialog(app.title.to_owned(), splash_bytes)
+        windows::splash::show_splash_dialog(locator.get_manifest_title(), splash_bytes)
     };
 
-    let install_result = install_impl(pkg, &root_path, &tx, start_args);
+    let install_result = install_impl(pkg, &locator, &tx, start_args);
     let _ = tx.send(windows::splash::MSG_CLOSE);
 
     if install_result.is_ok() {
@@ -148,13 +152,9 @@ pub fn install(pkg: &mut BundleZip, install_to: Option<&PathBuf>, start_args: Op
     Ok(())
 }
 
-fn install_impl(pkg: &mut BundleZip, root_path: &PathBuf, tx: &std::sync::mpsc::Sender<i16>, start_args: Option<Vec<&str>>) -> Result<()> {
+fn install_impl(pkg: &mut BundleZip, locator: &VelopackLocator, tx: &std::sync::mpsc::Sender<i16>, start_args: Option<Vec<&str>>) -> Result<()> {
     info!("Starting installation!");
 
-    let app_manifest = pkg.read_manifest()?;
-    let paths = create_config_from_root_dir(root_path);
-    let locator = VelopackLocator::new(paths, app_manifest);
-
     // all application paths
     let updater_path = locator.get_update_path();
     let packages_path = locator.get_packages_dir();
diff --git a/src/bins/src/commands/start_windows_impl.rs b/src/bins/src/commands/start_windows_impl.rs
index d914f7b1..d5fe9651 100644
--- a/src/bins/src/commands/start_windows_impl.rs
+++ b/src/bins/src/commands/start_windows_impl.rs
@@ -146,34 +146,31 @@ fn try_legacy_migration(root_dir: &PathBuf, manifest: &Manifest) -> Result<Velop
     // if started by legacy Squirrel, the working dir of Update.exe may be inside the app-* folder,
     // meaning we can not clean up properly.
     std::env::set_current_dir(&root_dir)?;
-
-    let _mutex = shared::retry_io(|| crate::windows::create_global_mutex(&manifest.id))?;
     let path_config = locator::create_config_from_root_dir(root_dir);
-    
     let package = locator::find_latest_full_package(&path_config.PackagesDir).ok_or_else(|| anyhow!("Unable to find latest full package."))?;
     
     warn!("This application is installed in a folder prefixed with 'app-'. Attempting to migrate...");
     let _ = shared::force_stop_package(&root_dir);
 
-    let current_dir = &path_config.CurrentBinaryDir;
-    if !Path::new(&current_dir).exists() {
+    // reset current manifest shortcuts, so when the new manifest is being read
+    // new shortcuts will be force-created
+    let mut modified_manifest = manifest.clone();
+    modified_manifest.shortcut_locations = String::new();
+    let locator = VelopackLocator::new(path_config, modified_manifest);
+    let _mutex = locator.try_get_exclusive_lock()?;
+
+    if !locator.get_current_bin_dir().exists() {
         info!("Renaming latest app-* folder to current.");
         if let Some((latest_app_dir, _latest_ver)) = shared::get_latest_app_version_folder(&root_dir)? {
-            fs::rename(latest_app_dir, &current_dir)?;
+            fs::rename(latest_app_dir, locator.get_current_bin_dir())?;
         }
     }
 
     info!("Removing old shortcuts...");
     win::remove_all_shortcuts_for_root_dir(&root_dir);
 
-    // reset current manifest shortcuts, so when the new manifest is being read
-    // new shortcuts will be force-created
-    let mut modified_manifest = manifest.clone();
-    modified_manifest.shortcut_locations = String::new();
-
     info!("Applying latest full package...");
     let buf = Path::new(&package.0).to_path_buf();
-    let locator = VelopackLocator::new(path_config, modified_manifest);
     let new_locator = super::apply(&locator, false, OperationWait::NoWait, Some(&buf), None, false)?;
 
     info!("Removing old app-* folders...");
diff --git a/src/bins/src/update.rs b/src/bins/src/update.rs
index a4e2a158..086d24e3 100644
--- a/src/bins/src/update.rs
+++ b/src/bins/src/update.rs
@@ -189,8 +189,7 @@ fn apply(matches: &ArgMatches) -> Result<()> {
     info!("    Exe Args: {:?}", exe_args);
 
     let locator = auto_locate_app_manifest(LocationContext::IAmUpdateExe)?;
-    #[cfg(target_os = "windows")]
-    let _mutex = shared::retry_io(|| windows::create_global_mutex(&locator.get_manifest_id()))?;
+    let _mutex = locator.get_exclusive_lock_blocking()?;
     let _ = commands::apply(&locator, restart, wait, package, exe_args, true)?;
     Ok(())
 }
diff --git a/src/bins/src/windows/util.rs b/src/bins/src/windows/util.rs
index 955fe5ee..fdb36f9d 100644
--- a/src/bins/src/windows/util.rs
+++ b/src/bins/src/windows/util.rs
@@ -78,21 +78,6 @@ impl Drop for MutexDropGuard {
     }
 }
 
-pub fn create_global_mutex(app_id: &str) -> Result<MutexDropGuard> {
-    let mutex_name = format!("velopack-{}", app_id);
-    info!("Attempting to open global system mutex: '{}'", &mutex_name);
-    let encodedu16 = super::strings::string_to_u16(mutex_name);
-    let encoded = PCWSTR(encodedu16.as_ptr());
-    let mutex = unsafe { CreateMutexW(None, true, encoded) }?;
-    match unsafe { GetLastError() } {
-        Foundation::ERROR_SUCCESS => Ok(MutexDropGuard { mutex }),
-        Foundation::ERROR_ALREADY_EXISTS => {
-            Err(anyhow!("Another installer or updater for this application is running, quit that process and try again."))
-        }
-        err => Err(anyhow!("Unable to create global mutex. Error code {:?}", err)),
-    }
-}
-
 pub fn expand_environment_strings<P: AsRef<str>>(input: P) -> Result<String> {
     use windows::Win32::System::Environment::ExpandEnvironmentStringsW;
     let encoded_u16 = super::strings::string_to_u16(input);
diff --git a/src/lib-rust/Cargo.toml b/src/lib-rust/Cargo.toml
index 747eb9ba..c05588b6 100644
--- a/src/lib-rust/Cargo.toml
+++ b/src/lib-rust/Cargo.toml
@@ -46,6 +46,7 @@ rand.workspace = true
 native-tls.workspace = true
 sha1.workspace = true
 sha2.workspace = true
+fslock.workspace = true
 
 # typescript
 ts-rs = { workspace = true, optional = true }
diff --git a/src/lib-rust/src/locator.rs b/src/lib-rust/src/locator.rs
index 16829869..cc63f30d 100644
--- a/src/lib-rust/src/locator.rs
+++ b/src/lib-rust/src/locator.rs
@@ -274,6 +274,33 @@ impl VelopackLocator {
     pub fn get_is_portable(&self) -> bool {
         self.paths.IsPortable
     }
+    
+    /// Attemps to open / lock a file in the app's package directory for exclusive write access.
+    /// Fails immediately if the lock cannot be acquired.
+    pub fn try_get_exclusive_lock(&self) -> Result<fslock::LockFile, Error> {
+        info!("Attempting to acquire exclusive lock on packages directory (non-blocking)...");
+        let packages_dir = self.get_packages_dir();
+        std::fs::create_dir_all(&packages_dir)?;
+        let lock_file_path = packages_dir.join(".velopack_lock");
+        let mut file = fslock::LockFile::open(&lock_file_path)?;
+        let result = file.try_lock_with_pid()?;
+        if !result {
+            return Err(Error::Generic("Could not acquire exclusive lock on packages directory".to_owned()));
+        }
+        Ok(file)
+    }
+
+    /// Attemps to open / lock a file in the app's package directory for exclusive write access.
+    /// Blocks until the lock can be acquired.
+    pub fn get_exclusive_lock_blocking(&self) -> Result<fslock::LockFile, Error> {
+        info!("Attempting to acquire exclusive lock on packages directory (blocking)...");
+        let packages_dir = self.get_packages_dir();
+        std::fs::create_dir_all(&packages_dir)?;
+        let lock_file_path = packages_dir.join(".velopack_lock");
+        let mut file = fslock::LockFile::open(&lock_file_path)?;
+        file.lock_with_pid()?;
+        Ok(file)
+    }
 
     fn path_as_string(path: &PathBuf) -> String {
         path.to_string_lossy().to_string()
diff --git a/src/lib-rust/src/manager.rs b/src/lib-rust/src/manager.rs
index 5fafff1a..817bb1db 100644
--- a/src/lib-rust/src/manager.rs
+++ b/src/lib-rust/src/manager.rs
@@ -295,6 +295,7 @@ impl UpdateManager {
     /// - If there is no delta update available, or there is an error preparing delta
     ///   packages, this method will fall back to downloading the full version of the update.
     pub fn download_updates(&self, update: &UpdateInfo, progress: Option<Sender<i16>>) -> Result<(), Error> {
+        let _mutex = &self.locator.try_get_exclusive_lock()?;
         let name = &update.TargetFullRelease.FileName;
         let packages_dir = &self.locator.get_packages_dir();