I noticed that older versions of mIRC report Windows 7 as Vista, rather than 7.

I had a look at the change log for $OS, but the last update was for Vista.

In what version of mIRC was $OS updated for Windows 7?

Thanks.

Probably on 7.0, couldn't test it but 7.1 has the change.

In general, the change will appear in the first release following the release of the OS.