diff --git a/launcher/FileSystem.cpp b/launcher/FileSystem.cpp
index 9e399bbfb..a39f44015 100644
--- a/launcher/FileSystem.cpp
+++ b/launcher/FileSystem.cpp
@@ -1691,4 +1691,30 @@ QString getPathNameInLocal8bit(const QString& file)
 }
 #endif
 
+QString getUniqueResourceName(const QString& filePath)
+{
+    auto newFileName = filePath;
+    if (!newFileName.endsWith(".disabled")) {
+        return newFileName;  // prioritize enabled mods
+    }
+    newFileName.chop(9);
+    if (!QFile::exists(newFileName)) {
+        return filePath;
+    }
+    QFileInfo fileInfo(filePath);
+    auto baseName = fileInfo.completeBaseName();
+    auto path = fileInfo.absolutePath();
+
+    int counter = 1;
+    do {
+        if (counter == 1) {
+            newFileName = FS::PathCombine(path, baseName + ".duplicate");
+        } else {
+            newFileName = FS::PathCombine(path, baseName + ".duplicate" + QString::number(counter));
+        }
+        counter++;
+    } while (QFile::exists(newFileName));
+
+    return newFileName;
+}
 }  // namespace FS
diff --git a/launcher/FileSystem.h b/launcher/FileSystem.h
index 23bf5f16e..66adf7a36 100644
--- a/launcher/FileSystem.h
+++ b/launcher/FileSystem.h
@@ -560,4 +560,6 @@ uintmax_t hardLinkCount(const QString& path);
 QString getPathNameInLocal8bit(const QString& file);
 #endif
 
+QString getUniqueResourceName(const QString& filePath);
+
 }  // namespace FS
diff --git a/launcher/minecraft/mod/Resource.cpp b/launcher/minecraft/mod/Resource.cpp
index 863b0165f..2a7626953 100644
--- a/launcher/minecraft/mod/Resource.cpp
+++ b/launcher/minecraft/mod/Resource.cpp
@@ -159,15 +159,14 @@ bool Resource::enable(EnableAction action)
         if (!path.endsWith(".disabled"))
             return false;
         path.chop(9);
-
-        if (!file.rename(path))
-            return false;
     } else {
         path += ".disabled";
-
-        if (!file.rename(path))
-            return false;
+        if (QFile::exists(path)) {
+            path = FS::getUniqueResourceName(path);
+        }
     }
+    if (!file.rename(path))
+        return false;
 
     setFile(QFileInfo(path));
 
diff --git a/launcher/minecraft/mod/ResourceFolderModel.cpp b/launcher/minecraft/mod/ResourceFolderModel.cpp
index aba0886e8..941e7ce58 100644
--- a/launcher/minecraft/mod/ResourceFolderModel.cpp
+++ b/launcher/minecraft/mod/ResourceFolderModel.cpp
@@ -215,9 +215,6 @@ bool ResourceFolderModel::setResourceEnabled(const QModelIndexList& indexes, Ena
         }
 
         auto new_id = resource->internal_id();
-        if (m_resources_index.contains(new_id)) {
-            // FIXME: https://github.com/PolyMC/PolyMC/issues/550
-        }
 
         m_resources_index.remove(old_id);
         m_resources_index[new_id] = row;
diff --git a/launcher/minecraft/mod/tasks/BasicFolderLoadTask.h b/launcher/minecraft/mod/tasks/BasicFolderLoadTask.h
index 23a2b649a..2bce2c137 100644
--- a/launcher/minecraft/mod/tasks/BasicFolderLoadTask.h
+++ b/launcher/minecraft/mod/tasks/BasicFolderLoadTask.h
@@ -7,6 +7,7 @@
 
 #include <memory>
 
+#include "FileSystem.h"
 #include "minecraft/mod/Resource.h"
 
 #include "tasks/Task.h"
@@ -50,6 +51,12 @@ class BasicFolderLoadTask : public Task {
 
         m_dir.refresh();
         for (auto entry : m_dir.entryInfoList()) {
+            auto filePath = entry.absoluteFilePath();
+            auto newFilePath = FS::getUniqueResourceName(filePath);
+            if (newFilePath != filePath) {
+                FS::move(filePath, newFilePath);
+                entry = QFileInfo(newFilePath);
+            }
             auto resource = m_create_func(entry);
             resource->moveToThread(m_thread_to_spawn_into);
             m_result->resources.insert(resource->internal_id(), resource);
diff --git a/launcher/minecraft/mod/tasks/ModFolderLoadTask.cpp b/launcher/minecraft/mod/tasks/ModFolderLoadTask.cpp
index 2094df4fc..501d5be13 100644
--- a/launcher/minecraft/mod/tasks/ModFolderLoadTask.cpp
+++ b/launcher/minecraft/mod/tasks/ModFolderLoadTask.cpp
@@ -36,6 +36,7 @@
 
 #include "ModFolderLoadTask.h"
 
+#include "FileSystem.h"
 #include "minecraft/mod/MetadataHandler.h"
 
 #include <QThread>
@@ -63,6 +64,12 @@ void ModFolderLoadTask::executeTask()
     // Read JAR files that don't have metadata
     m_mods_dir.refresh();
     for (auto entry : m_mods_dir.entryInfoList()) {
+        auto filePath = entry.absoluteFilePath();
+        auto newFilePath = FS::getUniqueResourceName(filePath);
+        if (newFilePath != filePath) {
+            FS::move(filePath, newFilePath);
+            entry = QFileInfo(newFilePath);
+        }
         Mod* mod(new Mod(entry));
 
         if (mod->enabled()) {