SharePoint / InoPath NaN error


I have a Form Library I am using to create Company Bills. I have a field in my Form which is used to calculate the VAT of the Bill items.

When I preview the Form it works grand but when I upload it to the Site and go to create a new Form the field which has the default value applied (ie the calculated VAT) it displays NaN (Not a Number) error.

If I submit the Form you can see for a split second that the value is then set and once I reopne the Form after submission it has the correct value displayed.

I changed the default Form opening on the Library to open in the client application and this resolved the issue but I cant keep it like this - various reasons but basically I need it to open in the browser.

Can anyone help with this issue or tell me why it's doing this?

Who is Participating?
Clay FoxDirector of Business IntegrationCommented:
It sounds like an issue with postback, which you can research and experiment with.  Browser forms try to limit the number of refreshes they do for performance.  It sound like initially there is not a value to multiply but it does not refresh once there is.

The lowtech method is to change it from a default and put an action on the total field that when it changes set the VaT field.  That probably would trigger the refresh as well. has more info on browser forms.
TugsolAuthor Commented:
Hi clayfox,

I've had a quick play around with it but it's still happening. I have tried setting it up using an initial value in the required fields as I had read that that can be an issue. It still happens even with a value having been set to begin with.

I then took the default value off the VAT field and created a Rule instead which sets the value when a required field changes. This didn't work and probably isn't what I'm after as I think a Rule only runs once and doesn't refresh?!?

I then reset the default value of the VAT field but removed the tick box to recalculate the value but still no joy.

Any other ideas? Or how else can I get the Form to refresh?

TugsolAuthor Commented:
Sorry, I think I misread the second half of your post. It was indeed an issue with the postback. I changed the postback option to Always for the control in question.

Thanks for your help!
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