Good evening. I've a strange problem with Mathcad 14 M020. I work with MS Windows Vista Business, where I've installed Mathcad 14 M020. I have McAfee as antivirus. The product works well, but when I start the McAfee utility for maintenance of the PC (cleaning registry, deleting temporary files, etc.) it seems that Mathcad loses some functionality. When I open it, it has apparently lost the possibility of accessing to external files (with and without Wizard option), as the product server could not start (indeed this is the message I receive). I solve the problem by using the "repair" option on Windows control panel, but it is strange. I've also asked to the PTC assistance, that helped me to solve the problem when it happens, but not to remove it (although when I asked to them I hadn't yet realized the causal link between McAfee routine running and Mathcad problem). Is there anybody that has similar troubles? It is not really a dramatic issue, but I would prefer to avoid these system problems (maybe it depends on the antivirus and/or the system, I don't know). Thanks in advance! Franco