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In order to help you as quickly as possible, before clicking Create Topic please provide as much of the following as you can (you can cut and paste this into your topic):
Nextcloud version (eg, 10.0.2): 11.0.2
Operating system and version (eg, Ubuntu 16.04): Ubuntu 16.04
Apache or nginx version (eg, Apache 2.4.25): 2.4.18
PHP version (eg, 5.6): 7.0.18
Is this the first time you’ve seen this error?: Yes
Can you reliably replicate it? (If so, please outline steps):
The issue you are facing:
After a heavy crash I’m rebuilding my Nextcloud. I restored my files (nextcloud-data) from a backup and use ownBackup to restore the database. Everything seems ok, the table oc_share seems to have proper content, but on the client side (i.e. web GUI) there are files but no entries under shared with you or shared with others.
How to refresh or recover this information?
I did
occ files:scan -v --all
occ mainenance:repair
sudo -u www-data php occ maintenance:repair
- Repair MySQL collation
- Repair mime types
- Repair legacy storages
- Remove asset cache
- Asset cache cleared.
- Generate ETags for file where no ETag is present.
- ETags have been fixed for 0 files/folders.
- Clean tags and favorites
- 0 tags of deleted users have been removed.
- 0 tags for delete files have been removed.
- 0 tag entries for deleted tags have been removed.
- 0 tags with no entries have been removed.
- Drop old database tables
31/31 [============================] 100% - Drop old background jobs
- Remove getetag entries in properties table
- Removed 0 unneeded “{DAV:}getetag” entries from properties table.
- Repair outdated OCS IDs
- Repair invalid shares
- Remove old share propagation app entries
- Remove old (< 9.0) calendar/contact shares
4/4 [============================] 100% - Fix permissions so avatars can be stored again
2/2 [============================] 100% - Remove shares of a users root folder
- Repair unmerged shares
- Move .step file of updater to backup location
- Add move avatar background job
- Repair step already executed
- Add preview cleanup background jobs
- Fix potential broken mount points
- 14 mounts updated
- Fix component of birthday calendars
- 44 birthday calendars updated.
- Insert ValueFix background job for each user
- Insert UUIDFix background job for user and group in batches
occ maintenance:data-fingerprint
The output of your Nextcloud log in Admin > Logging:
The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
The output of your Apache/nginx/system log in /var/log/____:
Remember, this information may be requested if it isn’t supplied; for fastest response please provide as much as you can 
Feel free to use a pastebin service, otherwise log files can be indented with 4 spaces on each line to present them in a friendlier way on the forum.