GL account creation issue - reg

hi guys,

i created a GL ACCOUNT "500001".

step 1: i created the PO and assigned the mentioned GL account ....it's working.

step 2 : I did the goods receipt it's working.

step 3 : When i try to to the invoice (MIRO) by using the created PO ....(which has GL ACCOUNT NO : 500001)...

I am getting the error : GL account not defined in chart of accounts..

please help.

REGARDS

Giri