Alex: Bob, I'm getting a warning dialog box about windows update from time to time? I suspect my laptop is infected with virus.

Bob: It sounds like virus infection to me.

Alex: Could you [come over/come by] my cubicle for a minute to look at my laptop?

What's the difference between come over and come by?

Thanks in advance!
It's not come over my cubicle!

It's come over to my cubicle.

It can be come by my cubicle, but usually it's just come by or come to my cubicle.

Could you come by for a minute?
Could you come to my cubicle for a minute?
Could you come over to my cubicle for a minute?

There's no significant difference in meaning that I detect between them. Maybe, as Goodman suggests, there is less urgency implied by the first of the three.

by: come to be together, besides
to: direction of movement
over: spatial jumpEmotion: smile
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Come over - has a more direct tone to the sentence.

Come by - tends to send a message which says "when you are available/ free".
 CalifJim's reply was promoted to an answer.
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