VB Script req plz - 2 .XLS files; remove duplicate account # found in second .XLS file.

Here is an easy one for the pros. Probably a quick VB Script?

I have uploaded the 2 following files.
bad_accounts.xls and MasterAccounts.xls
I am tasked with comparing 2 lists in Excel 2003. I need a simple 'search and destroy that line' operation.
Look up the first entry on the bad_accounts file (Column A). Cross reference this to the MasterAccounts list.
Once the account # is found in the (Column A) MasterAccounts list, it needs the entire row deleted from the MasterAccount list.

The bad_accounts list does not need to be altered. It serves only as reference for what needs to be removed from the master.
The only alteration I can make to the MasterAccounts list is that the duplicated Account# (from bad_accounts) can be deleted. It cant be altered beyond that because it gets run through a script right after it has been cleansed of the bad_account #s.

If I am not clear, I am sorry, ask questions if needed please.

As always, Thank you for your help. I would be lost with out my excelforum folks!

Additional and probably not-needed info.
Fact - None of these lines will be duplicated in their own sheet. They are all unique codes on their own sheet.
Fact - The account #s have different amount of characters per account # but they are also the only numbers that have 4 consecutive numerical characters or more.

Thank you