Hello I have Joomla 3.6.4
K2 2.7.0 and Simple Image gallery Pro 3.0.3
When I create a new K2 item, there are some images that are getting loaded automatically in the image gallery tab, without me uploading any file.
They are images from the server.
Also, when I try to upload a new image, I get
Error 0
An error has occurred.
Unknown Archive Type

It is a jpg file..

Can you please check? What can I do?

Thank you

I also noticed that in the media/k2/galleries
I have a folder with a weird name "584aabb24b719" and inside it there is a file
el-GR.labels.txt which is empty..
What do you suspect?

I just installed SIG Pro to version 3.0.8 and still get the same error..

In administrator/error_log I have
[22-Dec-2016 10:53:53 UTC] PHP Strict Standards: Declaration of K2Element::render() should be compatible with JFormField::render($layoutId, $data = Array) in /home/mysite/public_html/administrator/components/com_k2/elements/base.php on line 25
[22-Dec-2016 10:54:08 UTC] PHP Warning: preg_match(): Compilation failed: invalid range in character class at offset 7 in /home/mysite/public_html/administrator/components/com_k2/lib/class.upload.php on line 2910
[22-Dec-2016 10:54:08 UTC] PHP Warning: preg_match(): Compilation failed: invalid range in character class at offset 7 in /home/mysite/public_html/administrator/components/com_k2/lib/class.upload.php on line 2950
[22-Dec-2016 10:54:08 UTC] PHP Warning: preg_match(): Compilation failed: invalid range in character class at offset 7 in /home/mysite/public_html/administrator/components/com_k2/lib/class.upload.php on line 2977
[22-Dec-2016 10:54:08 UTC] PHP Warning: preg_match(): Compilation failed: invalid range in character class at offset 7 in /home/mysite/public_html/administrator/components/com_k2/lib/class.upload.php on line 3004
[22-Dec-2016 10:54:08 UTC] PHP Warning: preg_match(): Compilation failed: invalid range in character class at offset 7 in /home/mysite/public_html/administrator/components/com_k2/lib/class.upload.php on line 3022

Hope this can help to solve the problem!
Thank you

Can´t upload neither using K2 MASTER version
I also get
An error has occurred.
0 Unknown Archive Type
Unfortunately the error_log file in
public_html/administrator isn´t generated so I cant tell if the Warnings are the same.

Hi again,
in media/k2/galleries there are 162 files with this name el-GR.labels.txt, most of them empty. ONLY this file is inside the folder which is included, and there is no images in those cases.
Some el-GR.labels.txt have content, the ones that have content the content is like this:
some-picture-name.jpg|Title|<b>Description</b><br />You can use HTML as you can see!

Also when I enter a page in frontend I get this error:
There was a problem rendering your image gallery. Please make sure that the folder you are using in the Simple Image Gallery Pro plugin tags exists and contains valid image files. The plugin could not locate the folder: media/k2/galleries/1434

I see the folder 1434 doesn´t have images, only have the el-GR.labels.txt which is completely empty!

I do not do the upload of the content, image galleries etc. so I am not sure what they have done, but I dont think the client entered through FTP to create such files..
I am a little terrified! Is it normal or am I hacked? : /

Hello there,

3.0.3 is a bit behind, quite a lot actually.
I would recommend updating the extension.

Now I am at 3.0.8.
What can I do with the files
el-GR.labels.txt
and what can I do with the warning:
There was a problem rendering your image gallery. Please make sure that the folder you are using in the Simple Image Gallery Pro plugin tags exists and contains valid image files. The plugin could not locate the folder: media/k2/galleries/1434

The latest version is 3.1.0 furthermore since this is related to a commercial extension please open a ticket in our helpdesk so we can troubleshoot the issue.

Furthermore please include a link to the site and credentials as well in the ticket.