Hi,

I know that from vba a udf (and any other code called by that udf) may not
alter the worksheet in any way.

However i have an addin from another product, and it has functions that do
more than just return a value to that cell. Does this require a call to a
dll ??

I tried implementing an asynchronous call (to ADO) and wired up an event but
that just made excel crash.

Thanks Elliot