WPJohn

The same happens at my own host. Maldet detects the NinjaFirewall signatures as malware. Think we can fix this by changing the Maldet rules.

Thanks for the clear and fast answer!

Still the same:
string(0) ""

BUT:
Good news ?? The images are back! In frontend and backend! So it seems to be fixed again.
It seems the wp_cache_flush(); did the trick.

Very strange, still wondering what happened or what I missed in the process. As far as I might suspect the following happened:
1. update failed (probably because of blocking wp-admin with security tools);
2. the database upgrade was not finished;
3. Tried the fixes with cronjob and forced upgrade;
4. Cleared cloudflare cache, wp-supercache and autoptimize cache;
5. Restarted apache to clear opcache;
6. Did all things you said;
7. wp_cache_flush() worked;

I am running memcached, could it be the situation that memcached kept the object cache from the failed database upgrade all this time in the cache? This is what I suspect now, but could be wrong. I share this to help you and other readers.
I am really interested in your conclusion.

But I am glad it works again:) Thanks!

It shows:

string(0) ""

The first data is from wp_termmeta table indeed.
The second data is from the postmeta table. Which seems to be my category image.

Also in the backend > products > categories > my-category I see the Name, description, thumbnail and more fields. The ‘Category Term meta field’ also shows a thumbnail id. But the thumbnail field (where you should see an image) is empty. Really strange. Maybe this information helps already.

I will go try and change the description and report back if it really changes at all.

Okay thanks, that gives still some hope!

For example this one?
[Termmeta table]

metaid  | termid | metakey | metavalue
1026 | 2637 | thumbnail_id | 30141

Termid corresponds to a category.
The metavalue (30141) is my image.
[POSTmeta table]:

667053	30141	_wp_attached_file	aanbiedingen.jpg
 edit	667054	30141	_wp_attachment_image_alt	aanbiedingen
 edit	667055	30141	_wp_attachment_metadata	a:6:{s:5:"width";i:360;s:6:"height";i:230;s:4:"file";s:16:"aanbiedingen.jpg";s:5:"sizes";a:5:{s:9:"t...

That looks as if it still exists and is okay, if I am correct?
(the image data above is the correct category image)

Still the category images are gone after the update. In frontend and in backend.

Yes, it’s filled with a lot of data. 5089 rows. I see product attribute lines, lines like: a:3:{i:0;s:5:”46448″;i:1;s:5:”46449″;i:2;s:5:”46468″;} and lines like display_type and thumbnail_id

All checked green.

woocommerce_sessions: ?
woocommerce_api_keys: ?
woocommerce_attribute_taxonomies: ?
woocommerce_downloadable_product_permissions: ?
woocommerce_order_items: ?
woocommerce_order_itemmeta: ?
woocommerce_tax_rates: ?
woocommerce_tax_rate_locations: ?
woocommerce_shipping_zones: ?
woocommerce_shipping_zone_locations: ?
woocommerce_shipping_zone_methods: ?
woocommerce_payment_tokens: ?
woocommerce_payment_tokenmeta: ?

WC Update log:
06-15-2016 @ 17:05:14 – Queuing 2.6.0 – wc_update_260_options
06-15-2016 @ 17:05:14 – Queuing 2.6.0 – wc_update_260_termmeta
06-15-2016 @ 17:05:14 – Queuing 2.6.0 – wc_update_260_zones
06-15-2016 @ 17:05:14 – Queuing 2.6.0 – wc_update_260_zone_methods
06-15-2016 @ 17:05:14 – Queuing 2.6.0 – wc_update_260_refunds
06-15-2016 @ 17:05:14 – Queuing 2.6.0 – wc_update_260_db_version
06-15-2016 @ 17:05:16 – Running wc_update_260_options callback
06-15-2016 @ 17:05:16 – Finished wc_update_260_options callback
06-15-2016 @ 17:05:16 – Running wc_update_260_termmeta callback
06-15-2016 @ 17:05:16 – Finished wc_update_260_termmeta callback
06-15-2016 @ 17:05:16 – Running wc_update_260_zones callback
06-15-2016 @ 17:05:16 – Finished wc_update_260_zones callback
06-15-2016 @ 17:05:16 – Running wc_update_260_zone_methods callback
06-15-2016 @ 17:05:16 – Finished wc_update_260_zone_methods callback
06-15-2016 @ 17:05:16 – Running wc_update_260_refunds callback
06-15-2016 @ 17:05:16 – Finished wc_update_260_refunds callback
06-15-2016 @ 17:05:16 – Running wc_update_260_db_version callback
06-15-2016 @ 17:05:16 – Finished wc_update_260_db_version callback
06-15-2016 @ 17:05:16 – Data update complete

Thanks. One plugin (optimize seo image) blocked the process.
After disabling this plugin it worked.

But.. the missing category images aren’t back.
Also I tried the WooCommerce 2.6.1 upgrade, but that didn’t help.
I hope the missing images can be restored somehow.

Hello,
I also had updater problems. Probably because I hide wp-admin behind NinjaFirewall. So the new updater failed.
Now I lost about 400 category images. They are still on the server but not ‘connected’ to the categories anymore.

I tried the manual fixes:
1. Finding the cronjob with crontrol: I could not see the cronjob.
2. Adding alternate cron to wp-config: doesnt help.
3. Adding workaround code to functions.php and opening the specific url: it gives white screen. Maybe because it cannot find the cronjob anymore?

I hope I can get the categories images back with the 2.6.1 update. Or that someone else knows a fix.
Thanks in advance!

I think I found the problem:
Overlapping rules in the Table Rate Shipping plugin. Some postal codes did overlap. After fixing this I never had the problem again.

Are you guys also using this plugin? Then check the rules.
Or other plugins which have rules which are applied somewhere in the shopping process.

Your server needs php5-curl installed. Without this you will get white screen.

Here I found another person with the same problem: https://www.kriesi.at/support/topic/veiw-cart-blank-page-2
This topic has been created some hours ago, so it looks like this is a recent bug. Maybe something wrong in the latest Woocommerce versio(n) or certain plugins?

Bump. I also would like to know this.

I had this when the php5-curl module wasn’t installed on the server.

Apt-get install php5-curl did the trick. (Or yum, depending on your platform)