Can you ignore it?

As many might have met the error: "The referenced script on this Behaviour is missing!"
can it effect your game, in anykind of way which can ruin the game, or not let you "ship" it?

 

You should just remove the components from the objects. Then the error will no longer exist.

 

But to answer your question, no, it won't cause any actual problems. Worst it could do is slow your game down ever so slightly. Mostly, it just clutters up your Console.

 

It's a warning, not an error. Errors (red) must be fixed, warnings (yellow) can be ignored, but should be fixed. Especially in this case, where there's no reason not to fix it.

--Eric

 

Well, usually. Sometimes errors don't matter either....

 

Like the random Unity editor GUI errors?

I've stopped reporting them and now just hit clear.

 

I am, of course, referring to errors caused by the user...you can't even enter play mode until they're fixed, so it's pretty mandatory....

--Eric

 

That's only compile time errors. Runtime errors are quite different, and their impact on how things go can vary quite a bit.

Here's a curly one: at work on Friday one of the designers asked me to look into an error he was getting. Things were working as expected, but the error kept showing up in specific cases. I looked into it and fixed the error, and the program completely freaked out. The error had been stopping a script from executing, but because it had already put itself in a valid state nothing bad actually happened as a result. As soon as I "fixed"* it the script could then execute but, because it was now executing with obviously dodgy data (which hadn't been documented appropriately) it now behaved incorrectly and yet didn't throw an error.

* The clear answer here is that I didn't actually fix it. From a user perspective, though, I did indeed fix the problem that the error message pointed me at. Unfortunately it was a symptom of a higher level problem that wasn't being detected at all...