diff --git a/launcher/FileSystem.cpp b/launcher/FileSystem.cpp
index 75343e38f..cafc4f25a 100644
--- a/launcher/FileSystem.cpp
+++ b/launcher/FileSystem.cpp
@@ -815,25 +815,78 @@ QString NormalizePath(QString path)
     }
 }
 
-static const QString BAD_PATH_CHARS = "\"?<>:;*|!+\r\n";
-static const QString BAD_FILENAME_CHARS = BAD_PATH_CHARS + "\\/";
+QString removeDuplicates(QString a)
+{
+    auto b = a.split("");
+    b.removeDuplicates();
+    return b.join("");
+}
+
+static const QString BAD_WIN_CHARS = "\"?<>:*|\r\n";
+
+static const QString BAD_FAT_CHARS = "<>:\"|?*+.,;=[]!";
+static const QString BAD_NTFS_CHARS = "<>:\"|?*";
+static const QString BAD_HFS_CHARS = ":";
+
+static const QString BAD_FILENAME_CHARS = removeDuplicates(BAD_WIN_CHARS + BAD_FAT_CHARS + BAD_NTFS_CHARS + BAD_HFS_CHARS) + "\\/";
 
 QString RemoveInvalidFilenameChars(QString string, QChar replaceWith)
 {
     for (int i = 0; i < string.length(); i++)
         if (string.at(i) < ' ' || BAD_FILENAME_CHARS.contains(string.at(i)))
             string[i] = replaceWith;
-
     return string;
 }
 
-QString RemoveInvalidPathChars(QString string, QChar replaceWith)
+QString RemoveInvalidPathChars(QString path, QChar replaceWith)
 {
-    for (int i = 0; i < string.length(); i++)
-        if (string.at(i) < ' ' || BAD_PATH_CHARS.contains(string.at(i)))
-            string[i] = replaceWith;
+    QString invalidChars;
+#ifdef Q_OS_WIN
+    invalidChars = BAD_WIN_CHARS;
+#endif
 
-    return string;
+    // the null character is ignored in this check as it was not a problem until now
+    switch (statFS(path).fsType) {
+        case FilesystemType::FAT:
+            invalidChars += BAD_FAT_CHARS;
+            break;
+        case FilesystemType::NTFS:
+        /* fallthrough */
+        case FilesystemType::REFS:  // similar to NTFS(should be available only on windows)
+            invalidChars += BAD_NTFS_CHARS;
+            break;
+        // case FilesystemType::EXT:
+        // case FilesystemType::EXT_2_OLD:
+        // case FilesystemType::EXT_2_3_4:
+        // case FilesystemType::XFS:
+        // case FilesystemType::BTRFS:
+        // case FilesystemType::NFS:
+        // case FilesystemType::ZFS:
+        case FilesystemType::APFS:
+        /* fallthrough */
+        case FilesystemType::HFS:
+        /* fallthrough */
+        case FilesystemType::HFSPLUS:
+        /* fallthrough */
+        case FilesystemType::HFSX:
+            invalidChars += BAD_HFS_CHARS;
+            break;
+        // case FilesystemType::FUSEBLK:
+        // case FilesystemType::F2FS:
+        // case FilesystemType::UNKNOWN:
+        default:
+            break;
+    }
+
+    if (invalidChars.size() != 0) {
+        for (int i = 0; i < path.length(); i++) {
+            if (path.at(i) < ' ' || invalidChars.contains(path.at(i))) {
+                path[i] = replaceWith;
+            }
+        }
+    }
+
+    return path;
 }
 
 QString DirNameFromString(QString string, QString inDir)
diff --git a/launcher/MMCZip.cpp b/launcher/MMCZip.cpp
index a32c1f5d3..00658b42b 100644
--- a/launcher/MMCZip.cpp
+++ b/launcher/MMCZip.cpp
@@ -289,9 +289,7 @@ std::optional<QStringList> extractSubDir(QuaZip* zip, const QString& subdir, con
 
     do {
         QString file_name = zip->getCurrentFileName();
-#ifdef Q_OS_WIN
         file_name = FS::RemoveInvalidPathChars(file_name);
-#endif
         if (!file_name.startsWith(subdir))
             continue;
 
diff --git a/launcher/minecraft/Library.cpp b/launcher/minecraft/Library.cpp
index 2c3f2035f..4e30f72d1 100644
--- a/launcher/minecraft/Library.cpp
+++ b/launcher/minecraft/Library.cpp
@@ -51,6 +51,7 @@ void Library::getApplicableFiles(const RuntimeContext& runtimeContext,
 {
     bool local = isLocal();
     auto actualPath = [&](QString relPath) {
+        relPath = FS::RemoveInvalidPathChars(relPath);
         QFileInfo out(FS::PathCombine(storagePrefix(), relPath));
         if (local && !overridePath.isEmpty()) {
             QString fileName = out.fileName();
diff --git a/launcher/modplatform/flame/FlameInstanceCreationTask.cpp b/launcher/modplatform/flame/FlameInstanceCreationTask.cpp
index c0a95af89..a629cc15b 100644
--- a/launcher/modplatform/flame/FlameInstanceCreationTask.cpp
+++ b/launcher/modplatform/flame/FlameInstanceCreationTask.cpp
@@ -538,9 +538,7 @@ void FlameCreationTask::setupDownloadJob(QEventLoop& loop)
     }
     for (const auto& result : results) {
         auto fileName = result.fileName;
-#ifdef Q_OS_WIN
         fileName = FS::RemoveInvalidPathChars(fileName);
-#endif
         auto relpath = FS::PathCombine(result.targetFolder, fileName);
 
         if (!result.required && !selectedOptionalMods.contains(relpath)) {
diff --git a/launcher/modplatform/flame/FlameModIndex.cpp b/launcher/modplatform/flame/FlameModIndex.cpp
index 83a28fa2b..1ca9237f4 100644
--- a/launcher/modplatform/flame/FlameModIndex.cpp
+++ b/launcher/modplatform/flame/FlameModIndex.cpp
@@ -139,9 +139,7 @@ auto FlameMod::loadIndexedPackVersion(QJsonObject& obj, bool load_changelog) ->
     file.version = Json::requireString(obj, "displayName");
     file.downloadUrl = Json::ensureString(obj, "downloadUrl");
     file.fileName = Json::requireString(obj, "fileName");
-#ifdef Q_OS_WIN
     file.fileName = FS::RemoveInvalidPathChars(file.fileName);
-#endif
 
     ModPlatform::IndexedVersionType::VersionType ver_type;
     switch (Json::requireInteger(obj, "releaseType")) {
diff --git a/launcher/modplatform/modrinth/ModrinthInstanceCreationTask.cpp b/launcher/modplatform/modrinth/ModrinthInstanceCreationTask.cpp
index 72904d9b5..c0806a638 100644
--- a/launcher/modplatform/modrinth/ModrinthInstanceCreationTask.cpp
+++ b/launcher/modplatform/modrinth/ModrinthInstanceCreationTask.cpp
@@ -241,9 +241,7 @@ bool ModrinthCreationTask::createInstance()
 
     for (auto file : m_files) {
         auto fileName = file.path;
-#ifdef Q_OS_WIN
         fileName = FS::RemoveInvalidPathChars(fileName);
-#endif
         auto file_path = FS::PathCombine(root_modpack_path, fileName);
         if (!root_modpack_url.isParentOf(QUrl::fromLocalFile(file_path))) {
             // This means we somehow got out of the root folder, so abort here to prevent exploits
diff --git a/launcher/modplatform/modrinth/ModrinthPackIndex.cpp b/launcher/modplatform/modrinth/ModrinthPackIndex.cpp
index 4671a330d..6c3df0902 100644
--- a/launcher/modplatform/modrinth/ModrinthPackIndex.cpp
+++ b/launcher/modplatform/modrinth/ModrinthPackIndex.cpp
@@ -227,9 +227,7 @@ auto Modrinth::loadIndexedPackVersion(QJsonObject& obj, QString preferred_hash_t
     if (parent.contains("url")) {
         file.downloadUrl = Json::requireString(parent, "url");
         file.fileName = Json::requireString(parent, "filename");
-#ifdef Q_OS_WIN
         file.fileName = FS::RemoveInvalidPathChars(file.fileName);
-#endif
         file.is_preferred = Json::requireBoolean(parent, "primary") || (files.count() == 1);
         auto hash_list = Json::requireObject(parent, "hashes");
 
diff --git a/launcher/net/HttpMetaCache.cpp b/launcher/net/HttpMetaCache.cpp
index 648155412..d8b1c7636 100644
--- a/launcher/net/HttpMetaCache.cpp
+++ b/launcher/net/HttpMetaCache.cpp
@@ -84,9 +84,7 @@ auto HttpMetaCache::getEntry(QString base, QString resource_path) -> MetaEntryPt
 
 auto HttpMetaCache::resolveEntry(QString base, QString resource_path, QString expected_etag) -> MetaEntryPtr
 {
-#ifdef Q_OS_WIN
     resource_path = FS::RemoveInvalidPathChars(resource_path);
-#endif
     auto entry = getEntry(base, resource_path);
     // it's not present? generate a default stale entry
     if (!entry) {