diff --git a/Source/Core/Core/IOS/ES/Formats.cpp b/Source/Core/Core/IOS/ES/Formats.cpp
index 97eba84154..224776dcaf 100644
--- a/Source/Core/Core/IOS/ES/Formats.cpp
+++ b/Source/Core/Core/IOS/ES/Formats.cpp
@@ -419,12 +419,13 @@ SharedContentMap::SharedContentMap(Common::FromWhichRoot root) : m_root(root)
 
 SharedContentMap::~SharedContentMap() = default;
 
-std::string SharedContentMap::GetFilenameFromSHA1(const std::array<u8, 20>& sha1) const
+std::optional<std::string>
+SharedContentMap::GetFilenameFromSHA1(const std::array<u8, 20>& sha1) const
 {
   const auto it = std::find_if(m_entries.begin(), m_entries.end(),
                                [&sha1](const auto& entry) { return entry.sha1 == sha1; });
   if (it == m_entries.end())
-    return "unk";
+    return {};
 
   const std::string id_string(it->id.begin(), it->id.end());
   return Common::RootUserPath(m_root) + StringFromFormat("/shared1/%s.app", id_string.c_str());
@@ -442,9 +443,9 @@ std::vector<std::array<u8, 20>> SharedContentMap::GetHashes() const
 
 std::string SharedContentMap::AddSharedContent(const std::array<u8, 20>& sha1)
 {
-  std::string filename = GetFilenameFromSHA1(sha1);
-  if (filename != "unk")
-    return filename;
+  auto filename = GetFilenameFromSHA1(sha1);
+  if (filename)
+    return *filename;
 
   const std::string id = StringFromFormat("%08x", m_last_id);
   Entry entry;
@@ -455,7 +456,7 @@ std::string SharedContentMap::AddSharedContent(const std::array<u8, 20>& sha1)
   WriteEntries();
   filename = Common::RootUserPath(m_root) + StringFromFormat("/shared1/%s.app", id.c_str());
   m_last_id++;
-  return filename;
+  return *filename;
 }
 
 bool SharedContentMap::DeleteSharedContent(const std::array<u8, 20>& sha1)
diff --git a/Source/Core/Core/IOS/ES/Formats.h b/Source/Core/Core/IOS/ES/Formats.h
index e90cb089b4..6d53baf1fc 100644
--- a/Source/Core/Core/IOS/ES/Formats.h
+++ b/Source/Core/Core/IOS/ES/Formats.h
@@ -10,6 +10,7 @@
 #include <array>
 #include <cstddef>
 #include <map>
+#include <optional>
 #include <string>
 #include <vector>
 
@@ -217,7 +218,7 @@ public:
   explicit SharedContentMap(Common::FromWhichRoot root);
   ~SharedContentMap();
 
-  std::string GetFilenameFromSHA1(const std::array<u8, 20>& sha1) const;
+  std::optional<std::string> GetFilenameFromSHA1(const std::array<u8, 20>& sha1) const;
   std::string AddSharedContent(const std::array<u8, 20>& sha1);
   bool DeleteSharedContent(const std::array<u8, 20>& sha1);
   std::vector<std::array<u8, 20>> GetHashes() const;
diff --git a/Source/Core/Core/IOS/ES/NandUtils.cpp b/Source/Core/Core/IOS/ES/NandUtils.cpp
index fd586010e5..70c03bbb05 100644
--- a/Source/Core/Core/IOS/ES/NandUtils.cpp
+++ b/Source/Core/Core/IOS/ES/NandUtils.cpp
@@ -152,8 +152,8 @@ std::vector<Content> GetStoredContentsFromTMD(const TMDReader& tmd)
                [&tmd, &shared](const auto& content) {
                  if (content.IsShared())
                  {
-                   const std::string path = shared.GetFilenameFromSHA1(content.sha1);
-                   return path != "unk" && File::Exists(path);
+                   const auto path = shared.GetFilenameFromSHA1(content.sha1);
+                   return path && File::Exists(*path);
                  }
                  return File::Exists(
                      Common::GetTitleContentPath(tmd.GetTitleId(), Common::FROM_SESSION_ROOT) +
diff --git a/Source/Core/Core/IOS/ES/TitleManagement.cpp b/Source/Core/Core/IOS/ES/TitleManagement.cpp
index 487b799d99..1bfd229a96 100644
--- a/Source/Core/Core/IOS/ES/TitleManagement.cpp
+++ b/Source/Core/Core/IOS/ES/TitleManagement.cpp
@@ -665,8 +665,8 @@ IPCCommandResult ES::ExportTitleDone(Context& context, const IOCtlVRequest& requ
 ReturnCode ES::DeleteSharedContent(const std::array<u8, 20>& sha1) const
 {
   IOS::ES::SharedContentMap map{Common::FromWhichRoot::FROM_SESSION_ROOT};
-  const std::string content_path = map.GetFilenameFromSHA1(sha1);
-  if (content_path == "unk")
+  const auto content_path = map.GetFilenameFromSHA1(sha1);
+  if (!content_path)
     return ES_EINVAL;
 
   // Check whether the shared content is used by a system title.
@@ -689,7 +689,7 @@ ReturnCode ES::DeleteSharedContent(const std::array<u8, 20>& sha1) const
     return ES_EINVAL;
 
   // Delete the shared content and update the content map.
-  if (!File::Delete(content_path))
+  if (!File::Delete(*content_path))
     return FS_ENOENT;
 
   if (!map.DeleteSharedContent(sha1))
diff --git a/Source/Core/DiscIO/NANDContentLoader.cpp b/Source/Core/DiscIO/NANDContentLoader.cpp
index e6aca0ce79..b55efc413b 100644
--- a/Source/Core/DiscIO/NANDContentLoader.cpp
+++ b/Source/Core/DiscIO/NANDContentLoader.cpp
@@ -208,7 +208,7 @@ void CNANDContentLoader::InitializeContentEntries(const std::vector<u8>& data_ap
     {
       std::string filename;
       if (content.IsShared())
-        filename = shared_content.GetFilenameFromSHA1(content.sha1);
+        filename = *shared_content.GetFilenameFromSHA1(content.sha1);
       else
         filename = StringFromFormat("%s/%08x.app", m_Path.c_str(), content.id);