Daniel W

1 hour ago, agsteele said:

Had auto filing become enabled?

https://www.evernote.com/PersonalSettings.action

It looks that was really the issue. At least for now it works. 

1 hour ago, Babis1215 said:

For me also when sending an email to EN and at the subject I include #FolderName, it stores it and all letters become symbols.

When I use the add-on from Outlook, then it works fine

Not sure if others has the same issue 

No I know about # and @ ... but that isn't the case. I added a PDF but nothing else. Same to your answer @PinkElephant.
I am using Evernote since 2008, and it just started since a week or so. 
 

1 hour ago, agsteele said:

Had auto filing become enabled?

https://www.evernote.com/PersonalSettings.action

Yes, that was on. I disabled it now. Let's check it out. 

Emailed Notes go suddenly to the folder Readwise, even the Standard email folder is “Inbox”.
I changed the standard folder twice - in the hope the setting would overwrite. Nothing changed.

What is wrong? Where to search?