Was notified by 2 separate clients this morning that the XML generated via printing the electronic copies of T4's was rejected at CRA. The error received from CRA was the 'file contains errors and would not be submitted'. When reviewing with the client directly in GP, file verification and generation did not contain errors. It is only when uploading the XML to the CRA website do you become aware of this with no indication of what the error is.
Further investigation showed that if you open the generated XML directly, you will see an error similar to the below embedded somewhere in the file.

If you open the XML in Notepad, and search for "fileramendmentnote", you will see that there is only one tag line noted; an end tag line. There is no open tag line. This is what is preventing the client from submitting the file to CRA.
Further, in Notepad, when you locate the line, it is located within the file in the T4 Summary section right below where code indicates the file is an original file.
Error Noted below in Red
<rpt_tcd>O</rpt_tcd>
</fileramendmentnote>
<T4_TAMT>
<tot_empt_incamt>899072.98</tot_empt_incamt>
<tot_empe_cpp_amt>29078.09</tot_empe_cpp_amt>
<tot_empe_eip_amt>9841.78</tot_empe_eip_amt>
<tot_rpp_cntrb_amt>0.00</tot_rpp_cntrb_amt>
<tot_itx_ddct_amt>210957.39</tot_itx_ddct_amt>
<tot_padj_amt>0.00</tot_padj_amt>
<tot_empr_cpp_amt>29078.09</tot_empr_cpp_amt>
<tot_empr_eip_amt>11642.79</tot_empr_eip_amt>
</T4_TAMT>
</T4Summary>
We found that if you remove the end tag line and save the file, you will then be able to successfully upload the file to CRA. (this fix is only for original T4 submissions - not amended T4's)
Corrected XML code
<rpt_tcd>O</rpt_tcd>
<T4_TAMT>
<tot_empt_incamt>899072.98</tot_empt_incamt>
<tot_empe_cpp_amt>29078.09</tot_empe_cpp_amt>
**We have not tested/verified what will be noted if the T4 submission is an amended copy. **