Web query - dealing with time-out errors

I've built a macro that updates data in certain cells every 60 seconds by web query, then writes that data to a graph.
Sometimes the web query gives a time-out error (causing a message box to pop up), which causes the spreadsheet to freeze until you click the "ok" button.
I want to put some code at the start of my macro, to the extent of

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But I have no idea how to refer to that error box.
How do I do that? Or if there's a better way to deal with this, shoot!

For others with the same problem: I may have figured it out.
I stumbled across the

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commands. Also explained here.
I'll implement this and see if it does what I need.