if it's a new installation, you need to copy the DB tables named "__invoices_XXX"
and then you need to install the IM4 extension.

Thanks for the reply. I have copied all the tables and the folder pdfinvoices but the invoices, quotes, payments don't display. I can see the count in the "Export to CSV" button but they just don't display.

I have as well installed the system plugins and enabled them.

make sure also that you go to OPTIONS and select all your desired presets, and hit save. then try to refresh the page. let me know if that helps or it still doesn't work.

Yes I did. I changed the currency and business details.

if you open the javascript console, do you get any error?
can you try setting your joomla global "error reporting" status to "simple"?

I get a Warning: Trying to access array offset on value of type int in /usr/www/users/donato/new/administrator/components/com_invoices/models/invoice.php on line 34

I found the problem. The currency is the issue. When I change the currency to South African Rand, everything breaks invoices, payments, and quotes.

In fact, only the 4 first currencies on that seem to be working.

thanks for reporting this. Will take a look into it.