diff --git a/3d-viewer/3d_cache/3d_filename_resolver.cpp b/3d-viewer/3d_cache/3d_filename_resolver.cpp
index 8b175ad641..faa3d3c4d4 100644
--- a/3d-viewer/3d_cache/3d_filename_resolver.cpp
+++ b/3d-viewer/3d_cache/3d_filename_resolver.cpp
@@ -922,7 +922,7 @@ bool S3D_FILENAME_RESOLVER::ValidateFileName( const wxString& aFileName, bool& h
     // if we see the :\ pattern then it must be a drive designator
     if( pos0 != wxString::npos )
     {
-        size_t pos1 = aFileName.find( wxT( ":\\" ) ) );
+        size_t pos1 = aFileName.find( wxT( ":\\" ) );
 
         if( pos1 != wxString::npos && ( pos1 != pos0 || pos1 != 1 ) )
             return false;