Should errors in a database upgrade to sharepoint 2016 mean that the system wont work ?

Question

We are upgrading to Sharepoint 2016 ( from sharepoint 2013) using the database attach method.

We are using Mount-SPContentDatabase to upgrade the content database.

The log file from this generates a number of errors. A large number of these reference missing features., missing weparts, missing setup files etc. The official advice for these appears to be install the solution/customisation that contained the missing object. However in our case we dont have these solutions for sharepoint 2016 and cannot re-install them ( and dont want to, partly for licensing reasons) .

So the upgrade log contains multiple errors.

We do not plan to use the pages that refer to missing objects ( or will delete them at a later date).

The upgrade log file has an INFO message near the end that says

"Upgrade session failed. 21 errors and 123 warnings encountered"

Is it safe to ignore the message saying that the upgrade has "failed" and use the Sharepoint 2016 system ?

Answer 1

Did you follow this procedure - https://learn.microsoft.com/en-us/sharepoint/upgrade-and-update/overview-of-the-upgrade-process

See also this - https://learn.microsoft.com/en-us/answers/questions/158394/upgrade-sharepoint-2013-farm-to-sharepoint-2016-fa