diff --git a/host/platform/Windows/capture/D12/d12.c b/host/platform/Windows/capture/D12/d12.c
index 767d2c02..69d626a5 100644
--- a/host/platform/Windows/capture/D12/d12.c
+++ b/host/platform/Windows/capture/D12/d12.c
@@ -401,6 +401,9 @@ static bool d12_deinit(void)
   memset(&this->captureFormat, 0, sizeof(this->captureFormat));
   memset(&this->dstFormat    , 0, sizeof(this->dstFormat    ));
 
+  /* dirty rect history is no longer valid */
+  this->nbDirtyRects = 0;
+
   return result;
 }