Problem with opening ArcGIS 10 in ArcGIS 9.3

Discussion created by turacek on May 23, 2011
I´ve got one machine with ArcGIS 10 and other one with ArcGIS 9.3 and when i save mxd in ArcGIS 10 as ArcGIS 9.3 and after that i try to open it in ArcGIS 9.3 , I got next error: see attached jpeg

Before some time I usually did  saving(opening) and everything worked perfectly...

If somebody know what is bad give me know...