Metro DataVac M3 User Manual page 62

M3
A problem appears sometimes while the data is transferring with a USB cable. The
M3 display acts like a keyboard, so, in order to write numbers, the "num lock" key
must be activated. If your keyboard doesn't have the "num lock" key, you can still find
it by writing "visual keyboard" in the windows search bar, and activate it. If even there
the "num lock" key doesn't appear, the option key allows to access to a menu from
which you can activate the "num lock".
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