I can't help you as to why but hope you know you can access deleted files and move them to the required folder(s)

 

If you mean 'trash', they are not in my trash or recycle bin.

 

As stated, in Yahoo Mail, go to your Trash folder. That is where all Deleted Yahoo Mail goes. You can restore anyone you want to keep. Also check to see if any of your missing Emails have been moved to a different Archive Folder.

 

Do you check to make sure they actually ended up in the folder you intended ? When looking, are you choosing to show all folders?

 

yea, I'm sure. I had a couple folders that had 20-30 emails in it.....now all gone!

 

Hopefully you have backup copies of your mail. If 7 days haven't gone by since they're missing, Yahoo offers retrieval. Recover lost or deleted emails | Yahoo Help - SLN2552

 

7 days are long gone. Is there some setting somewhere that auto deletes after so many days? Or auto deletes if no more room?
Thanks again

 

You have 1000GB of storage so nothing should be deleted. Yahoo does delete self created folders that have been inactive for a long time.

 

I have been using yahoo mail and gmail for years. Ever since we started to get faster and faster internet along with competition between providers for better pricing.

Both have their quirks and anomalies. On many many occasions I have found missing messages in wrong folders. Sometimes they might be in spam, sometimes, through having earlier checked a message read earlier, it ends up deleted along with a new message I didn't want.
Try doing, if you remember content, sender, header or part of the message, a search for what you remember to see if it has ended up in some place other than where you had wanted to put it.

 

thanks, i'll keep digging.