logon failed

hi
i am using crystal reports9 in vb6 with access database.

i Created one report called rep_customer
and wroted code on button_click event to call report from vb

vbcode---------------

public sub cust_report_button_click
connect
Set r = New ADODB.Recordset
ReportNameVar = App.Path & "\reports\rep_customers.rpt"
r.Open "select * from cust ", c, adOpenDynamic, adLockOptimistic
Set report = crxApplication.OpenReport(ReportNameVar, 1)
report.Database.SetDataSource r
CRViewer91.ReportSource = report
Rep_form.ViewReport
Rep_form.Show
End Sub
------------------

it;s working fine

i created one more report Called Purchase_order based
on two tables (purchase_order,purchase_order_details)
and wroted code on button_click event to call report from vb

vbcode---------------

public sub Purchase_report_button_click
connect
Set r = New ADODB.Recordset
ReportNameVar = App.Path & "\reports\rep_purchase.rpt"

r.Open "select Purchase_order.pono,purchase_order.date,
Purchase_order_details.Product_code ,Purchase_order_details.product_description
from purchase_order,purchase_order_details
where purchase_order.pono=purchase_order_details.pono ", c, adOpenDynamic, adLockOptimistic

Set report = crxApplication.OpenReport(ReportNameVar, 1)
report.Database.SetDataSource r
CRViewer91.ReportSource = report
Rep_form.ViewReport
Rep_form.Show
End Sub
---------------------
i am getting error like
logon failed
Details:Ado Error Code 0x80040e4d
Microsoft Jet Database Engine
Description not a valid password
sql stated 3031

Report is working fine in Desiging and Preview of Crystal Designer Environment
i am sure no problem in database connection username and password
because i am using same connection for customer report.

i hope Only the Problem while Calling from vb6 when report having 2 tables
Where is the Problem ?how Can i solve this One
Can Any one Help meOpen the report and Do verify Database