Do you currently hold an active Electronic Filing Identification Number (EFIN) from the Internal Revenue Service? do I have one of these?

Is someone asking you for that?

TT is not licensed for use by paid tax preparers.

You can not use the Online versions or the personal Desktop Software to prepare returns for clients.  Intuit (the company that makes TurboTax) has three tax software product lines for paid preparers: ProSeries, Lacerte, and Intuit Tax Online. Here are links to their web sites.

http://proseries.intuit.com
http://lacerte.intuit.com
http://accountants.intuit.com/tax/online/

For a new preparer just starting out, ProSeries Basic is probably the most suitable.

And to prepare more than five e-files, you will need to sign up with the IRS as an ERO - an Electronic Returns Originator.  How to become an Authorized E-file Provider…..
http://www.irs.gov/Tax-Professionals/e-File-Providers-&-Partners/Become-an-Authorized-e-file-Provider 

FAQ for Tax Preparer Requirements
http://www.irs.gov/Tax-Professionals/Requirements-for-Tax-Return-Preparers:-Frequently-Asked-Questions 

Do you need a PTIN (Preparer Tax Identification Number)?
http://www.irs.gov/Tax-Professionals/Frequently-Asked-Questions:-Do-I-Need-a-PTIN%3F

Turbo Tax is an Authorized IRS e-file Provider and as such they have an EFIN ... individuals using the TT program do not have one of their own. https://www.irs.gov/tax-professionals/e-file-providers-partners/faqs-about-electronic-filing-indenti...

yes i hold a EFIN

If you are a paid tax pro then you cannot use any of the Turbotax programs.  You must use a professional tax program.