I downloaded EOD data for the default database ("quotes") from Yahoo, with check marks set for items for which there was no data (mostly options).
I did not find a way to delete those checked symbols from the database? How does one delete symbols for which there is no data en-masse?
Trading financial instruments, including foreign exchange on margin, carries a high level of risk and is not suitable for all investors. The high degree of leverage can work against you as well as for you. Before deciding to invest in financial instruments or foreign exchange you should carefully consider your investment objectives, level of experience, and risk appetite. The possibility exists that you could sustain a loss of some or all of your initial investment and therefore you should not invest money that you cannot afford to lose. You should be aware of all the risks associated with trading and seek advice from an independent financial advisor if you have any doubts.