POL00028439 - Letter from Ernest & Young, Post Office Auditors, to Dave Miller re Horizon Acceptance Testing

Evidence on official site

POL00028439
POL00028439

R. 2aSer .
Sl] ERNST& YOUNG = ——___ tector tome

1 Lambeth Palace Road
London SEI 7EU .

Mr D Miller ‘ 2, Wath Lawn 23 August 1999
Post Office Counters Ltd

Gavrelle House anor enpurt ov ICOAMK/KLR
2-14 Bunhill Row © Direct Li .
London lw —,.
ECLY 8HQ . duet,

Dear Mr Miller

HORIZON ACCEPTANCE TESTING

As auditors of The Post Office we have been asked by Post Office Counters Ltd to provide
you with our views in respect of certain accounting’ integrity issues arising from tests
performed by POCL on Horizon data in the live trial.

We have not performed any validation of the issues or testing of the data. Our views
expressed in this letter are based on information provided to us by POCL resulting from
their tests. This letter is not intended to provide any assurance over any data in the live trial
or over any results arising from tests of such data.

The live trial is limited to 323 outlets.” We make our comments on the assumption that this
sample of outlets will be representative of the full network of outlets.

The following issue, as described to us by POCL gives us concern as to the ability of POCL
to produce statutory accounts to a suitable degree of integrity. We understand that POCL
has attributed a severity rating of ‘High’ to this matter.

Incident 376. Data Integrity - In order to test the integrity of weekly polling of Horizon cash
account transactions, POCL are reconstructing a weekly total by outlet from daily Horizon
pollings. At present this control test is showing discrepancies in that certain transactions do
not record the full set of attributes and this results in the whole transaction being lost from
the daily polling.

We are informed that an incident-has also occurred where transactional data committed at
the counter has been lost by the Pathway system during the creation of the outlet cash
account and has not therefore been passed to TIP in the weekly cash account sub files.

Both types of incident result in a lack of integrity on each of the two data streams used by
POCL to populate its central accounting systems, We understand that the cash account data
stream is the primary feed for POCL's main ledgers and client reconciliation processes.

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