I personally have never used the E tax code.  If something is exempt, I skip the field and don't enter anything.

However, have you tried

C1020,2.0000,4.7500,9.50,GST,0,0,0,0
H1020,2.0000,25.0000,50.00,GST,0,0,0,0

I don't think it will work but it is the best approximation to the calculations of the E tax code.  The reason I don't think it will work is because there are no details in the Rate, Included and Refundable columns, but it might work.

If you were going to skip the sales tax you could use the following and I think that will import.  I didn't test these, I'm just going from memory.

C1020,2.0000,4.7500,9.50
H1020,2.0000,25.0000,50.00

Hi Richard,

Thanks for your reply.  I imported both of your suggestions.  They both did import, however, the tax code in the tax column was still blank.

Ideally I would like the E tax code to show up so that the imported invoices to look the same as if they were manually entered.  Do you have any other suggestions?

I also tried changing the default tax code for the customer to see if that would make a difference and imported all of the different files to see if any of them would show the E tax code, and that didn't work either.