Warning pops up when opening dwg file using AutoCAD Civil 3D 2010

Hello, We are using AutoCAD Civil 3D 2010 for our drawings in the office and I am new to this kind of software.
I got curious and navigated the software. My colleague was then trying to open a client’s .dwg file when this error message popped up on the screen, see below. We wondered why this was happening because I knew I didn’t touch the coordinate system and why were they using coordinate system ‘XY-IFT’. Anyway, anyone who can help us get rid of this error which was always popping up every time we open the drawing?

Warning
Warning: Drawing S: ENG-PROJECTS4101-D005-09-01_Timberline Trail Drainage6000-SurveyC3D2010Timberline.dwg was Created with a version of coordinate system ‘XY-IFT’ that is different from the version installed on your system. Coordinate conversion operations may generate incorrect results.
