I am trying to print an invoice for the first time in Odoo and keep getting error messages. I have installed the latest version of wkhtmltopdf which is one of the messages that appeared when trying to print. I have also looked through forums and have installed Python 2.7 as I understand that v3.0+ is not exactly supported and could also be a problem. I also made sure I has installed the latest version of reportlab. I am not sure what else I can do. Here is my error list:

Traceback (most recent call last):

File "/opt/odoo/addons/report/controllers/main.py", line 121, in report_download

response = self.report_routes(reportname, docids=docids, converter='pdf')

File "/opt/odoo/openerp/http.py", line 403, in response_wrap

response = f(*args, **kw)

File "/opt/odoo/addons/report/controllers/main.py", line 65, in report_routes

pdf = report_obj.get_pdf(cr, uid, docids, reportname, data=options_data, context=context)

File "/opt/odoo/openerp/api.py", line 241, in wrapper

return old_api(self, *args, **kwargs)

File "/opt/odoo/addons/report/models/report.py", line 198, in get_pdf

save_in_attachment = self._check_attachment_use(cr, uid, ids, report)

File "/opt/odoo/openerp/api.py", line 241, in wrapper

return old_api(self, *args, **kwargs)

File "/opt/odoo/addons/report/models/report.py", line 345, in _check_attachment_use

pdf = base64.decodestring(pdf)

File "/usr/lib/python2.7/base64.py", line 321, in decodestring

return binascii.a2b_base64(s)

TypeError: must be string or buffer, not None

Thank you in advance for your help!!