Add An Auto-number To The Table?

i'm importing a text file into a access table like this:

vb.net
sql.CommandText = "SELECT * INTO [tblMailList] FROM [Text;DATABASE=" & frmMain.FolderName & ";HDR=NO].[" & frmMain.TextBoxFileName.Text & "]"
sql.ExecuteNonQuery()

my question is what is the best way to add an autonumber to the table? i currently do it like this:

vb.net

sql.CommandText = "ALTER TABLE [tblMailList] ADD COLUMN [ID] AUTOINCREMENT;"
sql.ExecuteNonQuery()

but when the file is too large i get this error: "File sharing lock count exceeded. Increase MaxLocksPerFile registry entry."

and yes, i have tried to change the registry entry and it didn't work:

vb.net
My.Computer.Registry.SetValue("HKEY_LOCAL_MACHINESOFTWAREMicrosoftJet4.0EnginesJet 4.0", "MaxLocksPerFile", "9000000")