Upgrade to 2.16 (Latest version) fails

I clicked the button to update my piwik installation to the latest version and it has failed.

It looks like there is a problem with the images for the theme. None of the images are displayed correctly.

This is the error message I am receiving… Update error: SQLSTATE[HY000]: General error: 2006 MySQL server has gone away ???/

Anyone have any ideas on this error ??

see How do I fix the error "Mysql Server has gone away"? - Analytics Platform - Matomo

Can you check your server error logs for some interesting error message maybe?

for images, the .htacces in plugins directory may be culprit, no idea why it did update,
but this one got me stuck for a few min

Should I remove the .htaccess file? Is that what solved your problem?

[Tue Apr 12 13:45:28.709957 2016] [core:alert] [pid 11389] [client] /var/www/html/piwik/libs/.htaccess: AddHandler not allowed here, referer: Sign in - Piwik

I removed the .htaccess file and it now works correctly.

I had the same problem with the database, that gave me this error:
“MySQL server has gone away”

After I got this error, I manually updated the files to version 2.16.1.

But now I see the following error:

“Error: ViewDataTable ID ‘table’ is already in use”

Please, can anyone help me?

See: https://forum.matomo.org/t/viewdatatable-id-table-is-already-in-use/18837/25?u=matthieu