can someone answer this? i'm getting no help from going over the documentation over and over and over again. 3months and i still can't get this software to work with paypal.....jeeeezzzzzzz. this is the first time i received the IPN error. i am not getting any sign up email notifications nor is anyone that has made a purchase through paypal, nor is anyone getting redirected to the subscriptions. I had a friend try a paypal subscription purchase...this is what i got in the error log: paypal_r ERROR: IPN validation error: Paypal claims it is not-valid IPN transaction: [INVALID] transaction_subject => payment_date => 19:23:38 Aug 18, 2010 PDT subscr_id => I-R0JC86CE2695 last_name => Sheikh residence_country => US item_name => 1 Month Subscription 13th Floor payment_gross => -25.00 mc_currency => USD business => mikec@thirteenthfloor.us payment_type => instant protection_eligibility => Ineligible verify_sign => ACUe-E7Hjxmeel8FjYAtjnx-yjHAA0-cE46KPVGYZW8XHEbvVNF6aJle payer_email => info@uniquesources.com txn_id => 4AP65619B5029510T receiver_email => mikec@thirteenthfloor.us first_name => Michael parent_txn_id => 8UR69573030795501 payer_id => TZ6VR6N43PMQ8 receiver_id => ARD4K7T9FK43A reason_code => refund item_number => 1M payer_business_name => Unique Sources payment_status => Refunded payment_fee => -1.03 mc_fee => -1.03 btn_id => 19338557 mc_gross => -25.00 charset => windows-1252 notify_version => 3.0