After logging in with correct username and password in Anveo Web Portal, the login screen appears without any error message. This may be caused by different problems:
Login is successful, but no company is found for this user.
Check the Anveo User rights: The user requires at least one entry with rights for an existing company.
Synchronize and replicate rights after adding rights.
In an upgrade scenario, ACF Multilanguage table still is in wrong format. The table structure has been changed between versions 4.05 to 4.06.
Consult documentation Update Process & Changelog on how to merge data from old to new table structure.
The Anveo log is active, but the log folder does not exist or has not sufficient rights.
Check the log folder path and write rights (see documentation).