diff --git a/.clang-tidy b/.clang-tidy
index 69fe82afafb..135f35e4664 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -87,8 +87,11 @@ Checks: >
 # Treat warnings as errors for CI/CD
 WarningsAsErrors: false
 
-# Header filter to include project headers
-HeaderFilterRegex: '(Core|Generals|GeneralsMD|Dependencies)/.*\.(h|hpp)$'
+# Header filter to include project headers.
+# Match relative paths (Core/Foo.h, Core\Foo.h) and absolute ones (.../Core/Foo.h).
+# Accept both / and \ so Windows diagnostics are not dropped.
+HeaderFilterRegex: '(^|[/\\])(Core|GeneralsMD|Generals|Dependencies)[/\\].*\.(h|hpp)$'
+ExcludeHeaderFilterRegex: '(^|[/\\])(MaxSDK|_deps)[/\\]'
 
 # Check options for specific rules
 CheckOptions: