I followed this to upgrade from version 1.6.10 to 2.0: https://help.passbolt.com/hosting/upgrade/ce/upgrade-ce.html
But unfortunately after all was done and I refreshed the site, I also got this error:
Could not verify server key. Server code: That version of GPGAuth is not supported. (undefined)
(See also: [v2.0.0-rc2] That version of GPGAuth is not supported):
What helped was to change the collation:
mysql -u root -p
MariaDB [passbolt]> use passbolt;
MariaDB [passbolt]> ALTER TABLE file_storage CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
Query OK, 2 rows affected (0.04 sec)
Records: 2 Duplicates: 0 Warnings: 0
Refreshed site and working. Thought I let you know, because in “8. Run the migration script” in the upgrade tutorial – I don’t know if it supposed to – didn’t change the collation.