diff --git a/theseus/src/api/auth.rs b/theseus/src/api/auth.rs
index 362b8cd26..389d62c9b 100644
--- a/theseus/src/api/auth.rs
+++ b/theseus/src/api/auth.rs
@@ -57,7 +57,6 @@ pub async fn authenticate(
     Ok(credentials)
 }
 
-
 /// Refresh some credentials using Hydra, if needed
 /// This is the primary desired way to get credentials, as it will also refresh them.
 #[tracing::instrument]
diff --git a/theseus/src/api/jre.rs b/theseus/src/api/jre.rs
index b8398a360..21af1f6ec 100644
--- a/theseus/src/api/jre.rs
+++ b/theseus/src/api/jre.rs
@@ -54,8 +54,12 @@ pub async fn get_optimal_jre_key(profile: &Profile) -> crate::Result<String> {
         })?;
 
     // Get detailed manifest info from Daedalus
-    let version_info =
-        download::download_version_info(&state, version, profile.metadata.loader_version.as_ref()).await?;
+    let version_info = download::download_version_info(
+        &state,
+        version,
+        profile.metadata.loader_version.as_ref(),
+    )
+    .await?;
     let optimal_key = match version_info
         .java_version
         .as_ref()
diff --git a/theseus/src/api/profile.rs b/theseus/src/api/profile.rs
index bf22233af..d7c9c0c19 100644
--- a/theseus/src/api/profile.rs
+++ b/theseus/src/api/profile.rs
@@ -146,8 +146,12 @@ pub async fn run_credentials(
                 profile.metadata.game_version
             ))
         })?;
-    let version_info =
-        download::download_version_info(&state, version, profile.metadata.loader_version.as_ref()).await?;
+    let version_info = download::download_version_info(
+        &state,
+        version,
+        profile.metadata.loader_version.as_ref(),
+    )
+    .await?;
     let pre_launch_hooks =
         &profile.hooks.as_ref().unwrap_or(&settings.hooks).pre_launch;
     for hook in pre_launch_hooks.iter() {
diff --git a/theseus/src/api/settings.rs b/theseus/src/api/settings.rs
index a839f2c88..fdf3b92c6 100644
--- a/theseus/src/api/settings.rs
+++ b/theseus/src/api/settings.rs
@@ -20,5 +20,6 @@ pub async fn set(settings: Settings) -> crate::Result<()> {
     let state = State::get().await?;
     // Replaces the settings struct in the RwLock with the passed argument
     *state.settings.write().await = settings;
+    state.reset_semaphore().await; // reset semaphore to new max
     Ok(())
 }
diff --git a/theseus/src/state/mod.rs b/theseus/src/state/mod.rs
index 8cb27300b..4e7d3bded 100644
--- a/theseus/src/state/mod.rs
+++ b/theseus/src/state/mod.rs
@@ -41,7 +41,9 @@ pub struct State {
     /// Information on the location of files used in the launcher
     pub directories: DirectoryInfo,
     /// Semaphore used to limit concurrent I/O and avoid errors
-    pub io_semaphore: Semaphore,
+    pub io_semaphore: RwLock<Semaphore>,
+    /// Stored maximum number of sempahores of current io_semaphore
+    pub io_semaphore_max: RwLock<u32>,
     /// Launcher metadata
     pub metadata: Metadata,
     // TODO: settings API
@@ -80,8 +82,10 @@ impl State {
                         Settings::init(&directories.settings_file()).await?;
 
                     // Loose initializations
+                    let io_semaphore_max = settings.max_concurrent_downloads;
+
                     let io_semaphore =
-                        Semaphore::new(settings.max_concurrent_downloads);
+                        RwLock::new(Semaphore::new(io_semaphore_max));
 
                     // Launcher data
                     let (metadata, profiles) = tokio::try_join! {
@@ -112,6 +116,7 @@ impl State {
                     Ok(Arc::new(Self {
                         directories,
                         io_semaphore,
+                        io_semaphore_max: RwLock::new(io_semaphore_max as u32),
                         metadata,
                         settings: RwLock::new(settings),
                         profiles: RwLock::new(profiles),
@@ -158,4 +163,21 @@ impl State {
 
         Ok(())
     }
+
+    /// Reset semaphores to default values
+    /// This will block until all uses of the semaphore are complete, so it should only be called
+    /// when we are not in the middle of downloading something (ie: changing the settings!)
+    pub async fn reset_semaphore(&self) {
+        let settings = self.settings.read().await;
+        let mut io_semaphore = self.io_semaphore.write().await;
+        let mut total_permits = self.io_semaphore_max.write().await;
+
+        // Wait to get all permits back
+        let _ = io_semaphore.acquire_many(*total_permits).await;
+
+        // Reset the semaphore
+        io_semaphore.close();
+        *total_permits = settings.max_concurrent_downloads as u32;
+        *io_semaphore = Semaphore::new(settings.max_concurrent_downloads);
+    }
 }
diff --git a/theseus/src/state/profiles.rs b/theseus/src/state/profiles.rs
index 2eabb9c3c..50633ace6 100644
--- a/theseus/src/state/profiles.rs
+++ b/theseus/src/state/profiles.rs
@@ -10,8 +10,8 @@ use std::{
     collections::HashMap,
     path::{Path, PathBuf},
 };
-use tokio::fs;
 use tokio::sync::Semaphore;
+use tokio::{fs, sync::RwLock};
 
 const PROFILE_JSON_PATH: &str = "profile.json";
 
@@ -119,7 +119,7 @@ impl Profile {
     pub async fn set_icon<'a>(
         &'a mut self,
         cache_dir: &Path,
-        semaphore: &Semaphore,
+        semaphore: &RwLock<Semaphore>,
         icon: bytes::Bytes,
         file_name: &str,
     ) -> crate::Result<&'a mut Self> {
@@ -166,11 +166,11 @@ impl Profiles {
     #[tracing::instrument]
     pub async fn init(
         dirs: &DirectoryInfo,
-        io_sempahore: &Semaphore,
+        io_sempahore: &RwLock<Semaphore>,
     ) -> crate::Result<Self> {
         let mut profiles = HashMap::new();
+        fs::create_dir_all(dirs.profiles_dir()).await?;
         let mut entries = fs::read_dir(dirs.profiles_dir()).await?;
-
         while let Some(entry) = entries.next_entry().await? {
             let path = entry.path();
             if path.is_dir() {
diff --git a/theseus/src/state/projects.rs b/theseus/src/state/projects.rs
index d69c73841..6ad8e90de 100644
--- a/theseus/src/state/projects.rs
+++ b/theseus/src/state/projects.rs
@@ -10,7 +10,7 @@ use sha2::Digest;
 use std::collections::HashMap;
 use std::path::{Path, PathBuf};
 use tokio::io::AsyncReadExt;
-use tokio::sync::Semaphore;
+use tokio::sync::{RwLock, Semaphore};
 
 #[derive(Serialize, Deserialize, Clone, Debug)]
 pub struct Project {
@@ -160,7 +160,7 @@ async fn read_icon_from_file(
     icon_path: Option<String>,
     cache_dir: &Path,
     path: &PathBuf,
-    io_semaphore: &Semaphore,
+    io_semaphore: &RwLock<Semaphore>,
 ) -> crate::Result<Option<PathBuf>> {
     if let Some(icon_path) = icon_path {
         // we have to repoen the zip twice here :(
@@ -208,7 +208,7 @@ async fn read_icon_from_file(
 pub async fn infer_data_from_files(
     paths: Vec<PathBuf>,
     cache_dir: PathBuf,
-    io_semaphore: &Semaphore,
+    io_semaphore: &RwLock<Semaphore>,
 ) -> crate::Result<HashMap<PathBuf, Project>> {
     let mut file_path_hashes = HashMap::new();
 
diff --git a/theseus/src/util/fetch.rs b/theseus/src/util/fetch.rs
index 5b1a11010..c5384e285 100644
--- a/theseus/src/util/fetch.rs
+++ b/theseus/src/util/fetch.rs
@@ -5,7 +5,7 @@ use reqwest::Method;
 use serde::de::DeserializeOwned;
 use std::ffi::OsStr;
 use std::path::{Path, PathBuf};
-use tokio::sync::Semaphore;
+use tokio::sync::{RwLock, Semaphore};
 use tokio::{
     fs::{self, File},
     io::AsyncWriteExt,
@@ -16,7 +16,7 @@ const FETCH_ATTEMPTS: usize = 3;
 pub async fn fetch(
     url: &str,
     sha1: Option<&str>,
-    semaphore: &Semaphore,
+    semaphore: &RwLock<Semaphore>,
 ) -> crate::Result<Bytes> {
     fetch_advanced(Method::GET, url, sha1, semaphore).await
 }
@@ -25,7 +25,7 @@ pub async fn fetch_json<T>(
     method: Method,
     url: &str,
     sha1: Option<&str>,
-    semaphore: &Semaphore,
+    semaphore: &RwLock<Semaphore>,
 ) -> crate::Result<T>
 where
     T: DeserializeOwned,
@@ -41,9 +41,10 @@ pub async fn fetch_advanced(
     method: Method,
     url: &str,
     sha1: Option<&str>,
-    semaphore: &Semaphore,
+    semaphore: &RwLock<Semaphore>,
 ) -> crate::Result<Bytes> {
-    let _permit = semaphore.acquire().await?;
+    let io_semaphore = semaphore.read().await;
+    let _permit = io_semaphore.acquire().await?;
     for attempt in 1..=(FETCH_ATTEMPTS + 1) {
         let result = REQWEST_CLIENT.request(method.clone(), url).send().await;
 
@@ -90,7 +91,7 @@ pub async fn fetch_advanced(
 pub async fn fetch_mirrors(
     mirrors: &[&str],
     sha1: Option<&str>,
-    semaphore: &Semaphore,
+    semaphore: &RwLock<Semaphore>,
 ) -> crate::Result<Bytes> {
     if mirrors.is_empty() {
         return Err(crate::ErrorKind::InputError(
@@ -114,9 +115,11 @@ pub async fn fetch_mirrors(
 pub async fn write<'a>(
     path: &Path,
     bytes: &[u8],
-    semaphore: &Semaphore,
+    semaphore: &RwLock<Semaphore>,
 ) -> crate::Result<()> {
-    let _permit = semaphore.acquire().await?;
+    let io_semaphore = semaphore.read().await;
+    let _permit = io_semaphore.acquire().await?;
+
     if let Some(parent) = path.parent() {
         fs::create_dir_all(parent).await?;
     }
@@ -132,7 +135,7 @@ pub async fn write_cached_icon(
     icon_path: &str,
     cache_dir: &Path,
     bytes: Bytes,
-    semaphore: &Semaphore,
+    semaphore: &RwLock<Semaphore>,
 ) -> crate::Result<PathBuf> {
     let extension = Path::new(&icon_path).extension().and_then(OsStr::to_str);
     let hash = sha1_async(bytes.clone()).await?;
diff --git a/theseus_gui/src-tauri/src/api/profile.rs b/theseus_gui/src-tauri/src/api/profile.rs
index 353bcf474..a311884bb 100644
--- a/theseus_gui/src-tauri/src/api/profile.rs
+++ b/theseus_gui/src-tauri/src/api/profile.rs
@@ -56,7 +56,10 @@ pub async fn profile_run_wait(path: &Path) -> Result<()> {
 // for the actual Child in the state.
 // invoke('profile_run_credentials', {path, credentials})')
 #[tauri::command]
-pub async fn profile_run_credentials(path: &Path, credentials: Credentials) -> Result<u32> {
+pub async fn profile_run_credentials(
+    path: &Path,
+    credentials: Credentials,
+) -> Result<u32> {
     let proc_lock = profile::run_credentials(path, &credentials).await?;
     let pid = proc_lock.read().await.child.id().ok_or_else(|| {
         theseus::Error::from(theseus::ErrorKind::LauncherError(
diff --git a/theseus_playground/src/main.rs b/theseus_playground/src/main.rs
index bbd950d9b..76d4b304b 100644
--- a/theseus_playground/src/main.rs
+++ b/theseus_playground/src/main.rs
@@ -31,7 +31,9 @@ async fn main() -> theseus::Result<()> {
 
     // Initialize state
     let st = State::get().await?;
-    st.settings.write().await.max_concurrent_downloads = 10;
+    st.settings.write().await.max_concurrent_downloads = 5;
+    // Changed the settings, so need to reset the semaphore
+    st.reset_semaphore().await;
 
     // Clear profiles
     println!("Clearing profiles.");