strange error in formula

[iffi]

i was doing very simple plus minus, like this

=D4-D5-D6-D7+C9

BUT it was giving error of like this #VALUE, i m unable to understand why it is showing such behavior , any idea ?

 

[Jonmo1]

i m at home at the moment, i m having this problem at my office. suppose if any of them return FALSE, then what i need to do to solve this problem ? i m not permitted to use internet at office, otherwise it would be easy

Then you need to convert the Non Numbers to real numbers.

 

[iffi]

Thanks for ur time and contribution, i appreciate it, this problem is resolved myself.
actually in sheet1, in Cell D4, i was using this formula =if(sheet2!D4="","",sheet2!D4) and bcoz of this blank occuring by this formula , it was showing the error of #VALUE, i have solved it by changing the format, custom fromat = 0;-0; instead of this that if formula ,i changed the format and everything is fine now