Section 5-600 - Registration records; filing of1. The board of elections shall keep all registration records, when not in use at the polls for an election, at its main office, or a branch office designated by it. Such records shall be kept in locked ledgers or locked filing cabinets and shall not be removed from the office or branch office of the board of elections, except that the registration poll records of all voters entitled to vote at an election shall be delivered as provided in this chapter to the appropriate election district polling places for use at such election.2. The central file registration records shall be filed for the entire county using a system permitting location by name. Cancelled registration records shall be filed separately and shall be arranged in the same manner as current registration records.3. The registration poll records shall be classified by election districts, the records for each election district being filed according to street, by number, and alphabetically within any address or in the discretion of the board of elections they may be filed alphabetically by name of voter.4. Any registration record not completed because of the refusal of a board of inspectors to register an applicant shall be filed by the board of elections with the cancelled registration records as if the person affected had registered and his registration had been cancelled.5. After receipt thereof from a board of inspectors at the close of a period of local registration, the board of elections, before removing any records or blank forms from any ledger containing registration records of voters registered during such period, shall compare such records and blanks with the certificate filed by such board of inspectors. It shall investigate any discrepancy between such returned material and the information contained on such certificate and if such discrepancy is not satisfactorily resolved, it shall, at the request of any commissioner, make a written report thereof in triplicate and send one copy of such report to the district attorney and one to the state board of elections and keep the third copy on file at its office as a public record. The board of elections shall then remove the records and blanks from the ledgers and shall file them as provided herein.