we are trying to upgrade a CiviCRM 4.6.15 on Wordpress that comes from a multisite Drupal installation. This on WordPress is on a different server, but with the same DNS and Admin name. It works correctly but...
...if we try to upgrade to CiviCRM 4.7 (or 5.1) the procedure starts but does not go beyond a "dead screen" with a Retry & Skip button that do not work.
We fear that there were problems with exporting the DB from Drupal multisite. Please, where should we look for the error?
Attached the log file: https://pastebin.com/65fnAgMG
Thanks in advance for those who can help us.
1) as our SysAdmin (user3225453) replied, we've tried to follow Jaap's procedure below, but it's not working.
2) However this activity and the next Jaap' comment helped us to read better the LOGs:
the problem (if does not concern "not imported custom fields" as suspected by Jaap) could also be related to "PROFILE" (aka: "UF_Group", which are also found in the LOG)
Do you have any idea? what about if we delete all profiles from the previous installation and try a new update?