diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5b598bacf..983fece25 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -15,7 +15,7 @@ include(GtsamTesting)
 include(GtsamPrinting)
 
 # guard against in-source builds
-if(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_BINARY_DIR} AND NOT MSVC)
+if(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_BINARY_DIR})
   message(FATAL_ERROR "In-source builds not allowed. Please make a new directory (called a build directory) and run CMake from there. You may need to remove CMakeCache.txt. ")
 endif()