tcl exec ver command

I would like to exec windows commands with tcl exec, it works ok but
when I try to execute ver command to view the windows operating system
using tcl exec it returns an error:

catch {exec ver} results
puts "$results"

returns:

Could'nt execute "ver": no such file or directory.

How come it does not recognize ver command which it runs ok from the
dos command prompt please do advice

Martin W

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