diff --git a/src/client/component/download.cpp b/src/client/component/download.cpp
index 2cf1e450..49bca99f 100644
--- a/src/client/component/download.cpp
+++ b/src/client/component/download.cpp
@@ -8,6 +8,8 @@
 
 #include "game/ui_scripting/execution.hpp"
 
+#include "utils/hash.hpp"
+
 #include <utils/concurrency.hpp>
 #include <utils/http.hpp>
 #include <utils/io.hpp>
@@ -165,7 +167,7 @@ namespace download
 
 					const auto url = utils::string::va("%s/%s", base.data(), file.name.data());
 					console::debug("Downloading %s from %s: %s\n", file.name.data(), base.data(), url);
-					const auto data = utils::http::get_data(url, {}, {}, &progress_callback);
+					auto data = utils::http::get_data(url, {}, {}, &progress_callback);
 					if (!data.has_value())
 					{
 						menu_error("Download failed: An unknown error occurred, please try again.");
@@ -177,7 +179,7 @@ namespace download
 						return;
 					}
 
-					const auto& result = data.value();
+					auto& result = data.value();
 					if (result.code != CURLE_OK)
 					{
 						menu_error(utils::string::va("Download failed: %s (%i)\n", 
@@ -192,7 +194,7 @@ namespace download
 						return;
 					}
 
-					const auto hash = utils::cryptography::sha1::compute(result.buffer, true);
+					const auto hash = utils::hash::get_buffer_hash(result.buffer, file.name);
 					if (hash != file.hash)
 					{
 						menu_error(utils::string::va("Download failed: file hash doesn't match the server's (%s: %s != %s)\n", 
diff --git a/src/client/component/party.cpp b/src/client/component/party.cpp
index 8d3af0d2..9a484405 100644
--- a/src/client/component/party.cpp
+++ b/src/client/component/party.cpp
@@ -211,7 +211,11 @@ namespace party
 			}
 
 			const auto hash = utils::hash::get_file_hash(file);
-			hash_cache.insert(std::make_pair(file, hash));
+			if (!hash.empty())
+			{
+				hash_cache.insert(std::make_pair(file, hash));
+			}
+
 			return hash;
 		}
 
@@ -271,6 +275,7 @@ namespace party
 				}
 
 				const auto hash = get_file_hash(filename);
+				console::debug("hash != source_hash => %s != %s\n", source_hash.data(), hash.data());
 				if (hash != source_hash)
 				{
 					files.emplace_back(filename, source_hash);
@@ -327,6 +332,7 @@ namespace party
 				if (!has_to_download)
 				{
 					const auto hash = get_file_hash(file_path);
+					console::debug("has_to_download = %s != %s\n", source_hash.data(), hash.data());
 					has_to_download = source_hash != hash;
 				}
 
diff --git a/src/client/utils/hash.cpp b/src/client/utils/hash.cpp
index 56ad536c..2995c796 100644
--- a/src/client/utils/hash.cpp
+++ b/src/client/utils/hash.cpp
@@ -3,6 +3,7 @@
 #include "game/game.hpp"
 
 #include "hash.hpp"
+#include "component/console.hpp"
 
 #include <zlib.h>
 #include <utils/cryptography.hpp>
@@ -30,6 +31,8 @@ namespace utils::hash
 			game::DB_AuthHash empty_hash{};
 			if (!std::memcmp(header.hash.bytes, empty_hash.bytes, hash_size))
 			{
+				console::warn("Computing pakfile hash because its missing, this may take some time...\n");
+
 				hash_state state;
 				sha256_init(&state);
 
@@ -82,6 +85,40 @@ namespace utils::hash
 			hash.append(reinterpret_cast<char*>(&crc_value), sizeof(crc_value));
 			return utils::string::dump_hex(hash, "");
 		}
+
+		std::string get_pakfile_buffer_hash(std::string& buffer)
+		{
+			if (buffer.size() < sizeof(game::XPakHeader))
+			{
+				return {};
+			}
+
+			constexpr auto hash_size = sizeof(game::DB_AuthHash);
+			const auto header = reinterpret_cast<game::XPakHeader*>(buffer.data());
+
+			game::DB_AuthHash empty_hash{};
+			if (!std::memcmp(header->hash.bytes, empty_hash.bytes, hash_size))
+			{
+				console::warn("Computing pakfile hash because its missing, this may take some time...\n");
+				const auto hash_start = reinterpret_cast<std::uint8_t*>(buffer.data() + sizeof(game::XPakHeader));
+				const auto len = buffer.size() - sizeof(game::XPakHeader);
+				const auto hash = utils::cryptography::sha256::compute(hash_start, len, false);
+				std::memcpy(header->hash.bytes, hash.data(), sizeof(header->hash));
+			}
+
+			std::string hash = {header->hash.bytes, header->hash.bytes + hash_size};
+			return utils::string::dump_hex(hash, "");
+		}
+
+		std::string get_generic_buffer_hash(const std::string& buffer)
+		{
+			auto crc_value = crc32(0L, Z_NULL, 0);
+			crc_value = crc32(crc_value, reinterpret_cast<const std::uint8_t*>(buffer.data()), 
+				static_cast<std::uint32_t>(buffer.size()));
+			std::string hash;
+			hash.append(reinterpret_cast<char*>(&crc_value), sizeof(crc_value));
+			return utils::string::dump_hex(hash, "");
+		}
 	}
 
 	std::string get_file_hash(const std::string& file)
@@ -105,4 +142,16 @@ namespace utils::hash
 			return get_file_hash_generic(file_stream, file_size);
 		}
 	}
+
+	std::string get_buffer_hash(std::string& buffer, const std::string& filename)
+	{
+		if (filename.ends_with(".pak"))
+		{
+			return get_pakfile_buffer_hash(buffer);
+		}
+		else
+		{
+			return get_generic_buffer_hash(buffer);
+		}
+	}
 }
diff --git a/src/client/utils/hash.hpp b/src/client/utils/hash.hpp
index e67ed873..4e5c9e56 100644
--- a/src/client/utils/hash.hpp
+++ b/src/client/utils/hash.hpp
@@ -3,4 +3,5 @@
 namespace utils::hash
 {
 	std::string get_file_hash(const std::string& file);
+	std::string get_buffer_hash(std::string& buffer, const std::string& filename);
 }