This is the link I have my code from

w w w.vbaexpress.com/forum/showthread.php?46617-Solved-How-to-fast-write-Excel-VBA-array-contents-to-a-text-file!

I don't understand it very well. All I need is to find solution how to read from and write to large txt file (more then 600 000 rows and 20 columns) in Excel. I've tried already the code from the link you posted, but it takes forever to import text.