Company X has determined that it could issue $1000,- face value of bonds with an 8 % coupon paid semi annually and a five year maturity at $900 per bond. The marginal tax rate of the company is 38%. What is its after tax cost of debt?

So in my calculator (which is set on END)I do the following FV 1000 PMT 40 N 10 PV 900 CPT I/Y

I get then the error 5

If I do the same as above, however with -40 PMT I get the error 7.