I need a way to compare two spreadsheet and then remove duplicates - massive data sets

Hello,

I am not versed in formulas but I know there has to be a way to make this easier. I have one Excel sheet with titled Leads and one titled Current Clients. I know there are current clients on my leads list but the leads list has over 50,000 lines and my current client list has about 14,00. The only columns that are the same are the names and email address. I need a way to compare, see the duplicates, and then remove the duplicates from the Leads list. I tried Conditional Formatting but b/c of the massive amount of data the file keeps freezing up on me. I believe VLOOKUP might be the answer but I don't know how to initiate the formula or if it would work since in this instance.

I would love any help or advice I can get, thanks in advance!
Please let me know if what I am trying to explain is not clear.

My Apologies but I am having issues uploading the file but here is the break down:

I have combined my current client list with leads list into one excel sheet. My leads list is on sheet one with the following columns:
Company Name, Contact, Department, Titles, Email, Phone, Date Created

The current client list has:
Company Name, Contact, Email, Phone, Current Client - with Y/N as data

I am not sure how to create a macro that would look for sheet two clients/emails to compare to sheet one's to make sure there are not duplicates.

I hope this is semi clear for lack of excel file.
Thank you again for taking the time to try and help!

Yes! Sorry if my explanation was not helpful or convoluted.

I think it must be user error on my side b/c I created the macro and ran it but I don't see any removal taking place. I searched for a client in my client sheet and found it in the leads list. I think with my inexperience, I must be implementing it wrong. Thank you for taking the time to create the macro.

I created it, placed the code in the VBA and then placed the active cell on B1 and ran it, it processed it for a while but I don't see any difference, am I missing something?

Thank you so much, I really appreciate the help. I'm sorry for the delay, work got in the way of work. I will try this and see how it goes. I can't thank you enough for taking the time to help me and for all the explanations!

hello there! This help me in deleting duplicate spreadsheets hope this may help
http://duplicatefilesdeleter.com/

Thank you so much for this, I will definitely check this out and my project seems to be never ending.