I wrote an draft for an abstract that was saved on the conferenced website. I discussed the draft with my PhD supervisor, who told me he feels it's still too early in my PhD for me to think about presenting at conferences. So I left the draft abstract there on the website server for a few days hoping he would change his mind. When it came to the deadline for abstract submission I wrote to the conference organisers and asked for the unsubmitted abstract to be deleted. I was disappointed but it wasn't a big deal - there will be others. I forgot about it and moved on.

But my supervisor then came to me this week upset because apparently he checked up on me - he somehow obtained a copy of this draft from the conference organisers and started to accuse me of intending to submit the document without him knowing so. He said he was not happy with what was written and I would be damaging his reputation by sending it in. I at no stage received any receipt confirming I had submitted any documents, and the organisers can confirm for me that everything saved was deleted. I'm surprised by his reaction because I specifically checked with him about what I wrote in the draft, and when he said no, I deleted it.

Did I do anything wrong here? If anything hasn't my supervisor breached some kind of data protection legal act to have somehow obtained my draft from the conference server, and now using my expired draft against me when it was never meant to be submitted? I feel slightly uneasy about this whole situation.

So the conference has not deleted it and they have sent a confirmation email to your supervisor. It is not a big problem, you can talk or email to your supervisor and explain the same thing to him and tell him you would not submit an abstract without his permission in the future. I would suggest show him the email you have sent to the conference asking them to delete it. My supervisor is also very sensitive about conferences, he did not let me to send an abstract to any conference for a long time until I had good results. I know he would have a same reaction if I did what you have done. While some other profs do not have any problem with their students going to various conferences without results and ...

And maybe as a rule of thumb for the future, do not upload anything on the conference submission system until you're sure what you want to submit. It is usually better to work and polish the abstract offline, and upload and submit it only when you have the final version, approved by all authors.

As for now, Sara already gave good advice. Just explain and show your supervisor the email you sent to the conference.