Error executing code: Wrong argument types in variable assignment.

Dear All:

Upon posting PO, I have encountered this problem. :(

 Error executing code: Wrong argument types in variable assignment.

(S)\Classes\PurchFormLetter\specQty - line 3

(S)\Classes\PurchFormLetter\createParmUpdate - line 7

(S)\Classes\PurchFormLetter\prePromptInit - line 5

(S)\Classes\PurchFormLetter\mainOnServer - line 101

(C)\Classes\PurchFormLetter\main

(C)\Classes\FormFunctionButtonControl\Clicked

(C)\Classes\FormMenuButtonControl\Clicked

(C)\Classes\FormMenuButtonControl\Clicked

Error executing code: Wrong argument types in variable assignment.

(S)\Classes\PurchFormLetter\specQty - line 3

(S)\Classes\PurchFormLetter\createParmUpdate - line 7

(S)\Classes\PurchFormLetter\prePromptInit - line 5

(S)\Classes\PurchFormLetter\mainOnServer - line 101

(C)\Classes\PurchFormLetter\main

(C)\Classes\FormFunctionButtonContr'

Wish you could help me.

Thanks.

Heylin