mailResolveRecipient doesn't work

[luboan]

Hi all,
I'm writing little program sending e-mail to user from Powerbuilder.
To validate user name I use mailResolveRecipient function.

If mail session login was successful I enter user 1st and last name into sle_ controls. From this point i want to check user name:
*************************************
string ls_fname, ls_lname, ls_uname, ls_name

ls_fname = sle_first_name.Text
ls_lname = sle_last_name.Text

//Find if entered user info. is in the Globla E-mail list
mailReturnCode mRet
mailRecipient mRecip

mRecip.Name = ls_fname + ", " + ls_lname
mRet = mSes.mailResolveRecipient(mRecip.Name)
If mRet <> mailReturnSuccess! Then
MessageBox ("Invalid user name", ls_lname + ", " + ls_fname + " not found. Oracle User account can't be created.")
mses. mailLogoff()
DESTROY mses
close(parent)
Return
End if

If user name is correct and it is in Global E-mail list mailResolveRecipient works just fine at runtime and in exe.

Here is a problem!!!
if user name can’t be found in E-mail list mailResolveRecipient works at my computer as expected: window ‘Check Names’ pops up and I can find and select valid name from Global E-mail list. But when my exe. runs at any other computer ‘Check Names’ doesn’t appear and mailResolveRecipient returns mailReturnFailure!.

Can someone help me to find out why ‘Check names’ is showed up on my computer and not on all other?

We all at Windows XP, Powerbuilder10.5 and Outlook 2003.

Thanks. Will appreciate any help.