Widget

I’m not sure I understand what you’re problem is. Is your problem in the admin settings section? Or are you having problems actually subscribing an email address to a blog? If you could provide me with the browser and browser version you are using that would be helpful for me to figure out what is wrong. Also, if your site is live, a link to your site would also help me to look at the particular issue you are dealing with.

problems actually subscribing an email address to a blog
widget in sidebar,
opera, chrome last versions
Twenty Fourteen wp theme

mmm, i think thats conflict or something with one of my plugins https://profielder.ru/

That is possible. I would try to disable all plugins, then only enable osd-subscribe and see if it works or not. I am not sure how or why another plugin would cause a problem, but I can see that when a user tries to subscribe, the AJAX request is getting a 500 Internal Server Error which can generally be linked back to a PHP syntax error or an error simply causing PHP to fail (which could be caused by another plugin).

If this problem continues, I would recommend switching from OSD Subscribe and instead use OSD MailChimp Forms. You can create a free MailChimp account and that will allow you many subscribers and the ability to send many emails at the same time. It is considered bad practice to have a plugin send emails itself.

I hope this information helps.