Originally Posted by
st530
While not a perfect analogy, I was denied access earlier this year at EWR after completing GRU-IAH on one PNR and IAH-EWR on a separate PNR. I tried scanning both BPs at EWR and both times the GA wouldn't let me in (a bit strange because I initially got a green beep using the GRU-IAH BP but then the GA stared at her screen for a few moments and said "It says no access").
The gate readers at UCs, at least the Desko Penta (small rectangular blob with full-color screen) variety will go green on (virtually) any valid scan* -- that just acknowledges that the boarding pass was successfully read and communicated to the host computer.
AIMS, which is the software all of the United Clubs and I expect Polaris Lounges use to determine access [and to make sure other airlines get billed appropriately] is uncomfortably slow (it generally takes a few seconds to pop a result, during which time there is just a spinning circle on the screen. (Also FWIW: If someone scans another BP while AIMS is having a think, there's about a 50/50 chance that it will lock up and require the agent to restart)
When you scanned GRU-IAH at EWR the first popped result the agent would have seen would be something along the lines of "Invalid Airport" since AIMS is looking for either the origin or destination to match EWR in the IATA 2D barcode and an GRU-IAH BP fails that check .
When you scanned IAH-EWR at EWR the result after AIMS had a good think would be something like "no access" (I've never looked over an credential desk agent's shoulder in a PL but for a UC it's something along the lines of "no membership found" or "no entitlement" with a prompt for an alternate method like selling or scanning a OTP. (I'd like to expect that that prompt is suppressed at PLs) -- because here it passed the Boarding Pass validation sanity check (an EWR BP used at EWR) but neither the boarding pass nor the underlying reservation coded an entitlement.
*- Fun story: For our wedding my wife let me use an invitation that follows the UA boarding pass style + one of the old style ticket jackets. Each "boarding pass" included a unique "booking code" that was used for RSVPs and just to help complete the look I included a 1D barcode that duplicated the "booking code" (because I was too lazy to build an IATA-compliant 2D barcode, but not lazy enough to print the same barcode on every boarding pass...er...wedding invitation. At the time, a few UC agents tried scanning theirs. All went green, none granted lounge access
