Sum of calulation in subform not working?

[purextc]

Hi There,

I have a field in my subform that I'm calculating using a value from the main form [RE_Forecast_PPod]:

=[Cppm]/1000000*[Qinj_m3d]*1000/Forms!RE_Forecast_PPod!Bag_size_kg*7

This is working correctly.

What I then tried to do was create a Sum of this field in the footer of the subform to pass back to the main form :

Sum([Cppm]/1000000*[Qinj_m3d]*1000/Forms!RE_Forecast_PPod!Bag_size_kg*7)

I just keep getting an error on this sum. If I take out the part where I'm dividing by the field Forms!RE_Forecast_PPod!Bag_size_kg I can get it to work. Is this a syntax problem? My subform is [RE_Forecast_Inj subform]

Any help greatly appretiated.

Thanks

 

[AbsoluteAccess]

What is the error you are getting?

 

[purextc]

I just get the #error however if I substitute a value ie: 750 it works fine.

=Sum([Cppm]/1000000*[Qinj_m3d]*1000/750*7)

Please let me know if I can supply any additional information that would help. I'm new to access programming and also new to the forum.

Thanks!