Hallo. I installed the current version of Cadian 2012 on my machine (I7 - 8 GB ram - Windows 7 64 bit) and I am experiencing the following problems: - Frequent crashes of Windows explorer (as soon as I uninstall the program, the problem stops) - When I double-click to open a cad file, a violation error happens saying that the program can not be run; instead it is run but it does not open the drawing. - Some time, when I run the application, a windows says that I am not the Administrator, but I am an Administrator of the machine. I experience exactly the same behaviour on a different machine where I repeated the installation to double-check the problems. Due to the above I had to reconvert to Cadian 2011. Is there anything I can do to improve the situation? Thank you for your assistance. Regards, L.A.