FB image and FB no image

I've noticed that in last days when adding a blog with photo or a photo from my website on facebook, there is no thumbnail image. I've been doing lately small changes in the header html. whether it might have something to do with this problem? How to fix this? Please advice

FB with image:

FB with no image:

Have you tried to use the original file with no changes (header html) ? Does it works then?

I noticed the same. Facebook skips my logo and grabs the next large image on my homepage. 

 Sorry, what logo and what large image?

 Yes, I tried it. I uploaded original _header.html to check it out. Cleaned all cache and nothing. Even a few days ago it worked fine. What could be the reason?

 If you tried to use the original _header.html with no success, then your problem is not in this file. It would be really helpful to post here or send in PM your page URL, otherwise there might be a million guesses.

 Thanks. I send to you PM.

Apologies for interupting this topic. What I meant was that I had my site logo in my header and a large promo image (about 500 height and 1145 width px) on home page. Facebook skips my logo and grabs the logo and grabbed my promo image. That should be ideal when you want facebook to grab the first photo that you posted in your blog. 

Here's a link to check. Be aware that it takes about 24 hours (maybe that changed?) for facebook to scrape your page/photo and grab a new one. Hope you find this useful: 

https://developers.facebook.com/tools/debug 

When i share video  by clicking share button it is not working, so i have to manually post the link in the facebook page so the thumbnail will appear along the link. Last week i noticed this change in facebook.

 Thanks, this is an excellent tool!

Now this could be combined with my post about og tags.. 

http://www.boonex.com/forums/topic/Sharing-with-Google-problems.htm#188802

 Have you fixed this?

I have..

I'd like to know too lol

I have still this problem. But when I go to this tool https://developers.facebook.com/tools/debug and type my website I got this:

I don`t know what exactly 'og:url' I must fixed. But this could be a reason? Please advice

 Your going to be very, very surprised!!!

Making a video now, will upload in a bit.

 No need for this.

http://www.yoursite.com/blogs/entry/This-is-a-test-blog-again does not work,

http://www.yoursite.com/blogs/entry/This-is-a-test-blog-again/ this does.

 I try it but unfortunately not work for me :( I still can not see thumbnails when sharing.

anyone know how can I solve this problem?