Isn't this the same as the last issue? Please create standalone demos of this problem 
, it's not easy to sort through all the code on your pages. Thanks!

Certainly, 

Here is the page with one map - working
http://demo1.accountantwebsmiths.co.uk/maptest.php

Using the same code and creating new js vars for the second map the first one fail
http://demo1.accountantwebsmiths.co.uk/maptest2.php

Making sure - using same code again with new js vars for a third map the first and
second one fail
http://demo1.accountantwebsmiths.co.uk/maptest3.php

It use to work fine until last week - we had pages with 2 or 3 maps on them with no
problems :)

Sorry not sure what you meant by your first question being the same as last issue?

Here's a minimal demonstrator:

    http://econym.org.uk/gmap/issues/issue737.htm

Notes: 

The problem only occurs in v2.129a onwards.

The problem goes away if you allow time for the infowindow code module to load before
opening the infowindow in the second map.

Thanks, Mike.

Are there any workarounds for this problem? Can anyone help? 

Specify 2.128e instead of 2 in your script tag.

Just wanted to say thanks to everyone for posting their comments on this. I was 
getting the same error and going mad trying to solve it. Such a relief to see others 
with the issue....ahh I can sleep sound tonight with out this in my head :-) 

I've specified v2.128e and that's fixed it for now. 

Many, many thanks you helpful people!

Ditto - the change to 2.128e works great in overcoming this problem. THANKS for the
advice.

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Can someone help define how to specify the 2.128e in the script tag?

Change v=2 to v=2.128e

>Can someone help define how to specify the 2.128e in the script tag?

You probably have a Javascript include line like the following - you can see the
changed version number in it:

<script src="http://maps.google.com/maps?file=api&amp;v=2.128e&amp;key=*****  
type="text/javascript"></script>

I just encountered this problem and found a workaround - use setTimeout() to stagger
the execution of showInfoWindow so that they are called 500 ms apart. 

It's somewhat of a hack, but might come in handy for someone that doesn't want to use
bleeding edge code. 

Some time ago I did experiment with the delay function but found it too much inconsistent between browser and 
hardware models. It can just alleviate.

I read that this should work, too. I experimented with setTimout() but couldnt get it
to work for me. I have multiple instances of a map per page (up to 8 in one case),
and it wasnt clear that setTimout() worked for multiple events - at least, I didnt
pursue it any further. 

I made a separate setTimeout call for each map with a 500ms delay. 

i.e. 

setTimeout( function(){map1.showInfoWindow("Test1");}, 500 );
setTimeout( function(){map2.showInfoWindow("Test2");}, 1000 );
setTimeout( function(){map3.showInfoWindow("Test3");}, 1500 );

I found this worked about 95% of the time, but sometimes still triggered the error. I
ended up ditching this solution and am just using 2.128e for the time being.

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