Thanks for your responses. It started appearing suddenly on Friday and daily since then & when I boot the PC. I do have my PC & laptop in a network but, as it happens, they are rarely switched on at the same time. I do not get the "net command" box open on my laptop.
No, or at least I don't think so. I never have to log in as I leave no passwords for booting - I am me and the administrator. This has been the same since I have owned the PC and yet it is only now that "net command" has started appearing.
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