diff --git a/reactos/drivers/video/videoprt/videoprt.c b/reactos/drivers/video/videoprt/videoprt.c
index 04d7a8c57e1..d3547ee68b0 100644
--- a/reactos/drivers/video/videoprt/videoprt.c
+++ b/reactos/drivers/video/videoprt/videoprt.c
@@ -492,7 +492,7 @@ IntVideoPortFindAdapter(
       DeviceVideoBuffer,
       REG_SZ,
       DeviceExtension->RegistryPath.Buffer,
-      DeviceExtension->RegistryPath.Length);
+      DeviceExtension->RegistryPath.Length + sizeof(UNICODE_NULL));
 
    RtlWriteRegistryValue(
        RTL_REGISTRY_DEVICEMAP,