Hi Nigel,

The reason for being in automatic mode initially is to perform a one
time setting of constants in the model. I then would like to switch to
manual mode to iterate through the simulation senario.


It is best to take control yourself: switch to manual, change your
constants, then do application.calculate.

Using Range.calculate may be causing you a problem because it does not
calculate (as Excel normally does) in dependency order.
Agreed but excel manually calculates left to right and top to bottom and
the arrangement of the spreadsheet is in this order.

Using Sheet calculate assumes that all precedents for that sheet have
been correctly calculated.
This is currently my problem as the sheets are not calculating.

Admitedly the design of this model is not ideal, however this code
worked fine until yesterday. Excel seem to be ignoring the call to
calculate specific ranges and limited amounts of rows. Anymore comments
are welcome, however I am reluctant to rearrange the model unless it is
a last resort.


If you dont want to rearrange the model then just go for permanent Manual
mode and call application.calculate once per iteration.

Or find out what you have changed in the model that has caused the problem.
Or find out where the calculation time is being spent.


regards
Charles
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