Hi Dave,

Yes it does, however, the problem is not related to clicking buttons as such.

The gantt chart I speak of is dynamically recreated (destroyed and re-built)
each time the worksheet it is on is activated. This all works fine when only
one excel window is open. However, when two windows are open, any action that
causes the gantt chart worksheet to be reactivated can cause the error I
mentioned in my first post. The 'refresh' code I mentioned previously is just
one example of code which causes the gantt chart's worksheet to be activated.
However, the error does not occur on a regular basis - only sometimes (seems
to be at random)

I have been in touch with Microsoft Technical Support who are investigating
my problem at this current point time. Hopefully they will be able to shed
some light on what is going wrong.

I will try and post the resolution up if the problem gets solved.

Cheers all - especially dave

DAvid