my bank accepts only stock market transactions with ISIN code, not ticker codes.

There ought to be central register. For some reason this site gives no response

http://isin.net/free-isin-lookup-search/

What about http://www.morningstar.com/ ?

I doubt it's what you are looking for ! Sorry

ISIN search is provided by a fistful of german "direct" banks, e.g.

http://www.onvista.de/anleihen/snapshot.html?ISIN=USP17625AD98

enter company name up right

http://www.comdirect.de/inf/waehrungen/detail/uebersicht.html?ID_INSTRUMENT=1515776

enter company name up left (Kurssuche)

try, if you need some assistance let me know.

There is no central register. Each country is responsible for assigning its own ISIN codes to securities, usually based upon an older local scheme such as CUSIP or SEDOL. If the OP identifies which country or exchange he/she's interested in it might be easier to give a helpful reply.

There is no central register. Each country is responsible for assigning its own ISIN codes to securities, usually based upon an older local scheme such as CUSIP or SEDOL. If the OP identifies which country or exchange he/she's interested in it might be easier to give a helpful reply.

individual countries can have additional specific codes but ISINs are unique and used internationally. by the way, every CUSIP can also be identified by an assigned ISIN but not vice versa.