[httpitis]

...my co-workers using windows

ftfy.

[djackson]

Why would he need to explain it to the windows that are using his coworkers?

Also, it's very unclear to me what that the situation you are describing entails.

/s

Grammatically, your sentence is no less ambiguous.

[httpitis]

oh man, thursday evening, a couple of glasses of wine, and here I thought I was the grammar nazi :)

[ajscherer]

"my windows-using coworkers" would be a better fix.

[code_duck]

"...my coworkers who use Windows" makes more sense.

[austintaylor]

my windows-using coworkers.