NASL reporting back errors

During scans I see a lot of:

lib  nasl:MESSAGE:2019-11-27 11h44.14 utc:44749: [44749](/var/lib/openvas/plugins/gb_default_credentials_options.nasl:92) script_get_preference_file_content: could not get  size of file from preference Credentials file:
lib  nasl:MESSAGE:2019-11-27 11h44.15 utc:44780: [44780](/var/lib/openvas/plugins/gb_default_credentials_options.nasl:92) script_get_preference_file_content: could not get  size of file from preference Credentials file:

What’s missing/not set here?
GVM11