diff --git a/build/lib/propertyInitOrderChecker.js b/build/lib/propertyInitOrderChecker.js
index 14c0e2cbd6c..8c287dbd852 100644
--- a/build/lib/propertyInitOrderChecker.js
+++ b/build/lib/propertyInitOrderChecker.js
@@ -257,7 +257,7 @@ for (const file of program.getSourceFiles()) {
     if (!file || file.isDeclarationFile) {
         continue;
     }
-    const relativePath = path.relative(path.dirname(TS_CONFIG_PATH), file.fileName);
+    const relativePath = path.relative(path.dirname(TS_CONFIG_PATH), file.fileName).replace(/\\/g, '/');
     if (ignored.has(relativePath)) {
         continue;
     }
diff --git a/build/lib/propertyInitOrderChecker.ts b/build/lib/propertyInitOrderChecker.ts
index 2c3090d8dce..d83b8c3fa2d 100644
--- a/build/lib/propertyInitOrderChecker.ts
+++ b/build/lib/propertyInitOrderChecker.ts
@@ -239,7 +239,7 @@ for (const file of program.getSourceFiles()) {
 		continue;
 	}
 
-	const relativePath = path.relative(path.dirname(TS_CONFIG_PATH), file.fileName);
+	const relativePath = path.relative(path.dirname(TS_CONFIG_PATH), file.fileName).replace(/\\/g, '/');
 	if (ignored.has(relativePath)) {
 		continue;
 	}