diff --git a/openxlsx2.Rproj b/openxlsx2.Rproj
index 9d06b5e0d..9d81b2878 100644
--- a/openxlsx2.Rproj
+++ b/openxlsx2.Rproj
@@ -1,4 +1,5 @@
 Version: 1.0
+ProjectId: 9a8f65e4-b71b-46f7-b985-4ed325fa6ab5
 
 RestoreWorkspace: Default
 SaveWorkspace: Default