I believe that this is a linked account and you can't post directly to it.  You have to enter the AP invoices that created the balance. 

Sorry, I don't do a lot of postings. I would then have to enter each invoice that creates the balance, but how do I reverse it from the allocated account as this amount would of been included in our previous year end. The original entry on the previous y/e was posted as a Pay Later as per below.

DR - 5730 (vehicle expenses)  - $58.03

DR - 2375 (GST) - $2.90

CR - 2100 (accounts payable) - $60.93

When I entered the totals from the Trial Balance, I just put the total of the payables as one which is probably not right. 

Thanks for your help!

Perhaps I'm unclear on what you are doing.

You're starting a new year on a new computer and you're taking the previous balances and manually entering them?  There is a balance for AP on your TB that needs to be entered

Or are you wanting to pay an invoice that was part of the AP balance you entered when you manually entered the amounts from the TB?

When I entered the balances from my Trial Balance, I entered the total into AP. The payment has come out of our bank account so I need to clear it from AP. 

This is where the issue with the linked account occurs when you are trying to clear balances. 

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