I am trying to install the IDL virtual machine to execute a program I need. For this, I've tried installing the evaluation versions of IDL 7.0 and 7.1, (over windows 7 64 bit), because thay contain the IDL vm inside. The installation process seems to finish ok, but when I execute the .sav, i get the following message: "Update to a development license of IDL, Clic to continue" and when i clic the box, i get another message: "Variable is undefined: PATH_UNIT." I really don't know where is the error. Other collegues use this program over the IDL 7.0 and it works fine. Maybe it is the Windows 7, or something with the license, or maybe something with the configuration. Can anyone help me with this? Many thanks in advance.