Yes, you're right... its the Payable/Receivable changed to Main Tax/Main Receivable and working good now.

OK so it seems that you have configure tax account as payable/receivable which is probably wrong. But any the template should be assumed an not required field to be filled.

Something wrong not sure but when I remove the Item Tax it posted fine.
So now I'm trying to see if I did something wrong with the tax setup.

It looks like the lines to pay do not have a maturity date. I do not see how it is possible but any the report should not fail in this case and just not try to format the empty maturity date.

Hello, I'm new to Tryton and just testing out the capabilities and functions it offers.
But I'm stuck with an error on "posting" the invoice. (see below)

Does anyone encounter the same issue?
I have followed the installation process base on the documentation.

Application Error
Warning:
Traceback (most recent call last):
  File "/usr/local/lib/python37/dist-packages/trytond/wsgipy", line 116, in dispatch_request
    return endpoint(request, **requestview_args)
  File "/usr/local/lib/python37/dist-packages/trytond/protocols/dispatcherpy", line 48, in rpc
    request, database_name, *requestrpc_params)
  File "/usr/local/lib/python37/dist-packages/trytond/wsgipy", line 83, in auth_required
    return wrapped(*args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/protocols/wrapperspy", line 131, in wrapper
    return func(request, pool, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/protocols/dispatcherpy", line 181, in _dispatch
    result = rpcresult(meth(*c_args, **c_kwargs))
  File "/usr/local/lib/python37/dist-packages/trytond/modules/sale_payment/accountpy", line 175, in post
    super(Invoice, cls)post(invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/model/modelviewpy", line 740, in wrapper
    return func(cls, records, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/model/workflowpy", line 37, in wrapper
    result = func(cls, filtered, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/commission_waiting/invoicepy", line 17, in post
    super(Invoice, cls)post(invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/model/modelviewpy", line 740, in wrapper
    return func(cls, records, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/model/workflowpy", line 37, in wrapper
    result = func(cls, filtered, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/commission/invoicepy", line 37, in post
    super(Invoice, cls)post(invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/sale/invoicepy", line 19, in wrapper
    func(cls, invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/sale/invoicepy", line 79, in post
    super(Invoice, cls)post(invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/purchase/invoicepy", line 20, in wrapper
    func(cls, invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/purchase/invoicepy", line 92, in post
    super(Invoice, cls)post(invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/model/modelviewpy", line 740, in wrapper
    return func(cls, records, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/model/workflowpy", line 37, in wrapper
    result = func(cls, filtered, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/account_fr_chorus/accountpy", line 114, in post
    super(Invoice, cls)post(invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/model/modelviewpy", line 740, in wrapper
    return func(cls, records, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/model/workflowpy", line 37, in wrapper
    result = func(cls, filtered, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/account_invoice_stock/accountpy", line 18, in post
    super()post(invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/model/modelviewpy", line 740, in wrapper
    return func(cls, records, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/model/workflowpy", line 37, in wrapper
    result = func(cls, filtered, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/account_deposit/invoicepy", line 30, in post
    super(Invoice, cls)post(invoices)
  File "/usr/local/lib/python37/dist-packages/trytond/model/modelviewpy", line 740, in wrapper
    return func(cls, records, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/model/workflowpy", line 37, in wrapper
    result = func(cls, filtered, *args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/account_invoice/invoicepy", line 1474, in post
    invoiceprint_invoice()
  File "/usr/local/lib/python37/dist-packages/trytond/modules/account_invoice/invoicepy", line 1381, in print_invoice
    InvoiceReportexecute([selfid], {})
  File "/usr/local/lib/python37/dist-packages/trytond/modules/account_invoice/invoicepy", line 2629, in execute
    return super()execute(ids, data)
  File "/usr/local/lib/python37/dist-packages/trytond/report/reportpy", line 165, in execute
    oext, content = cls_execute(records, data, action_report)
  File "/usr/local/lib/python37/dist-packages/trytond/modules/account_invoice/invoicepy", line 2607, in _execute
    result = super(InvoiceReport, cls)_execute(records, data, action)
  File "/usr/local/lib/python37/dist-packages/trytond/report/reportpy", line 181, in _execute
    return clsconvert(action, clsrender(action, report_context))
  File "/usr/local/lib/python37/dist-packages/trytond/modules/account_invoice/invoicepy", line 2624, in render
    return super()render(*args, **kwargs)
  File "/usr/local/lib/python37/dist-packages/trytond/report/reportpy", line 276, in render
    data = templategenerate(**report_context)render()
  File "/usr/local/lib/python37/dist-packages/relatorio/templates/basepy", line 35, in render
    selfevents, method=method, encoding=encoding, out=out)
  File "/usr/local/lib/python37/dist-packages/relatorio/templates/opendocumentpy", line 1179, in __call__
    selfxml_serializer(writer(stream)), encoding=encoding, out=writer)
  File "/genshi/outputpy", line 58, in encode
    for chunk in iterator:
  File "/genshi/outputpy", line 241, in __call__
    for kind, data, pos in stream:
  File "/genshi/outputpy", line 671, in __call__
    for kind, data, pos in stream:
  File "/genshi/outputpy", line 776, in __call__
    for kind, data, pos in chain(stream, [(None, None, None)]):
  File "/genshi/outputpy", line 596, in __call__
    for ev in stream:
  File "/usr/local/lib/python37/dist-packages/relatorio/templates/opendocumentpy", line 1071, in __call__
    for kind, data, pos in stream:
  File "/genshi/filters/i18npy", line 691, in __call__
    for kind, data, pos in stream:
  File "/genshi/template/basepy", line 638, in _include
    for event in stream:
  File "/genshi/template/markuppy", line 327, in _match
    for event in stream:
  File "/genshi/template/basepy", line 598, in _flatten
    result = _eval_expr(data, ctxt, vars)
  File "/genshi/template/basepy", line 289, in _eval_expr
    retval = exprevaluate(ctxt)
  File "/genshi/template/evalpy", line 178, in evaluate
    return eval(selfcode, _globals, {'__data__': data})
  File "<string>", line 585, in <Expression '__relatorio_escape_invalid_chars(format_date(linematurity_date, invoicepartylang))'>
  File "/usr/local/lib/python37/dist-packages/trytond/report/reportpy", line 332, in format_date
    return langstrftime(value, format=format)
  File "/usr/local/lib/python37/dist-packages/trytond/ir/langpy", line 545, in strftime
    return valuestrftime(format)
AttributeError: 'NoneType' object has no attribute 'strftime'