I am having the same error message when trying to upload XML file. I talked to Quickbooks support 2 weeks ago and its and issue on their end and they are working on it. They said the will notify everyone once its resolved.

Error: We are unable to process your submission because we did not detect a T619 electronic transmittal record.

I have followed the latest updates on QBO post and I am getting the following error when I try to submit the XML through Represent a Client:
"Missing mandatory field on the summary - Filer Name".

Has anyone got this error yet? How do I fix this?

Please go to Payroll Settings>Federal TAX> Add REP ID 

Download the XTML file gain and submit to CRA. This should work.

Hope this Helps. 

Have a good one. 

Please go to Payroll Settings>Federal TAX> Add REP ID 

Download the XTML file gain and submit to CRA. This should work.

Hope this Helps. 

Have a good one. 

I am having the same problem, I tried yesterday 3 times again today and still no luck. Deadline is fast approached need this resolved.

Did you try the steps in these instructions?

https://quickbooks.intuit.com/learn-support/en-ca/help-article/update-products/changes-t4-t4a-t5018-...

I did. However, note that the error is not related with the RepId field. I opened the XML and I can confirm that the RepId is there.

The error is the following:
"Missing mandatory field on the summary - Filer Name".
It seems that the "Filer Name" is the missing field in the XML.

This is the error I am getting as well. QB will not generate the XML file as there is an "&" in my company name.

I have filed for the past 24 years using the same company name and have never had an issue.