'Conversion error' trying to upload to KWL

Hello (and help!).

Having successfully published from Scrivener (from an iMac running 10.9.5) to KDP, I am trying to do the same on KWL, but keep getting ‘an error occurred during conversion’ and the signpost to the EPUB Validator., which then gives this message (screenshot also attached):

ERROR OPS/content.opf 41 38 date value ‘2015/06/15’ is not valid as per w3.org/TR/NOTE-datetime: [For input string: “2015/06/15”] is not an integer

Unfortunately Kobo have not been of much help. I’ve searched online/here but found nothing similar to this, and I do not possess the level of knowledge to ‘figure it out’.

If it helps, when I create the .epub file and save it to my desktop, the iBooks icon appears on it. This just happens automatically, without me doing anything.

Also, I tried to upload a .mobi file (as Kobo says it can convert them), but exactly the same error message occurred

Help with this would be much appreciated. Thanks!
EPUB Validator (beta) Results.jpeg

On the link you provide, it says the date format has to follow exact punctuation:

Your date format and punctuation is YYYY/MM/DD.

If you change the / to a - , does it work?

Thanks Briar Kit, it does work now - phew! I did look at the Meta Data settings and changed the date, but admit I didn’t use the – to test it. That’s a huge help. :smiley:

Really pleased for you. Good luck.