CiviCRM Community Forums (archive)

Actually found the cause of the problem.

We modified the *label* column of the 'recur_frequency_units' option in the CiviCRM database.
The out-of-box 'label' column has the following entries:
day, week, month, year.

We customized the 'label' column to have
daily, weekly, monthly, yearly
to match our custom message on the Contribution pages.

Such customization on the 'label' made the assignToTemplate( ) function in
CRM/Contribute/Form/ContributionBase.php sending
'daily', or 'weekly', or 'monthly' or 'yearly' to PayPal Pro.
And thus PayPal returns error message.

A closer look at around line 592 in the assignToTemplate( ) function of the
ContributionBase.php showed the $frequencyUnits is getting the 'label' entries
of the 'recur_frequency_units' option:

$frequencyUnits =  CRM_Core_OptionGroup::values( 'recur_frequency_units' );

I think the original intend is for $frequencyUnits to get the 'value' entries of the 'recur_frequency_units' option.
The 'value' entries of the 'recur_frequency_units' option are
day, week, month, year.
And the function call to get $frequencyUnits should be

$frequencyUnits =  CRM_Core_OptionGroup::values( 'recur_frequency_units',
/* $flip = */ false, /* $grouping = */ false, /* $localize = */ false, /* $condition = */ null,
/* $valueColumnName = */ 'value');

The above modification allows CiviCRM developer using any custom 'label' on the
Contribution page while passing the correct billing period to PayPal.
So the above change fixed our problem.

Thanks for the great framework.

Filed a bug report as CRM-8504:
http://issues.civicrm.org/jira/browse/CRM-8504

Thanks.