diff --git a/src/CalcViewModel/Common/NavCategory.cpp b/src/CalcViewModel/Common/NavCategory.cpp
index 463f4301..6af89959 100644
--- a/src/CalcViewModel/Common/NavCategory.cpp
+++ b/src/CalcViewModel/Common/NavCategory.cpp
@@ -53,22 +53,6 @@ wchar_t* towchar_t(int number)
     return _wcsdup(wstr.c_str());
 }
 
-extern "C"
-{
-    WINADVAPI LSTATUS APIENTRY RegGetValueW(
-        _In_ HKEY hkey,
-        _In_opt_ LPCWSTR lpSubKey,
-        _In_opt_ LPCWSTR lpValue,
-        _In_ DWORD dwFlags,
-        _Out_opt_ LPDWORD pdwType,
-        _When_(
-            (dwFlags & 0x7F) == RRF_RT_REG_SZ || (dwFlags & 0x7F) == RRF_RT_REG_EXPAND_SZ || (dwFlags & 0x7F) == (RRF_RT_REG_SZ | RRF_RT_REG_EXPAND_SZ)
-                || *pdwType == REG_SZ || *pdwType == REG_EXPAND_SZ,
-            _Post_z_) _When_((dwFlags & 0x7F) == RRF_RT_REG_MULTI_SZ || *pdwType == REG_MULTI_SZ, _Post_ _NullNull_terminated_)
-            _Out_writes_bytes_to_opt_(*pcbData, *pcbData) PVOID pvData,
-        _Inout_opt_ LPDWORD pcbData);
-}
-
 bool IsGraphingModeAvailable()
 {
     static bool supportGraph = Windows::Foundation::Metadata::ApiInformation::IsMethodPresent("Windows.UI.Text.RichEditTextDocument", "GetMath");