Hi Gunther Hebein,

In order make ONLYOFFICE + FlinkISO work, consider following steps:

Your On-premise FlinkISO application should be able to communicate with ONLYOFFICE server. If not, to resolve this:-

1. Check if your firewall is not blocking external HTTP or HTTPS ports.
2. Check if you are using static IP or qualified domain, if not ONLYOFFICE will not work.
3. Document may not exists
4. Make sure you have added correct directory permissions to app/webroot/files folder and documents are getting uploaded
5. Use IP address instead of domain.
6. Try to ping your FlinkISO server from ONLYOFFICE server & vice-a-varsa

You can also refer to ONLYOFFICE Troubleshooting options here :

https://api.onlyoffice.com/editors/troubleshooting

Also, try adjusting /etc/onlyoffice/documentserver/local.json file to following
​
​"services": {
   "CoAuthoring": {
     "sql": {
       "type": "postgres",
       "dbHost": "localhost",
       "dbPort": "5432",
       "dbName": "onlyoffice",
       "dbUser": "onlyoffice",
       "dbPass": "onlyoffice"
     },
     "token": {
       "enable": {
         "request": {
           "inbox": false,
           "outbox": false
         },
         "browser": false
       },
       "inbox": {
         "header": "Authorization"
       },
       "outbox": {
         "header": "Authorization"
       }
     },
     "secret": {
       "inbox": {
         "string": "add_your_string_here"
       },
       "outbox": {
         "string": "add_your_string_here"
       },
       "session": {
         "string": "add_your_string_here"
       }
     }
   }
},
"rabbitmq": {
   "url": "amqp://guest:guest@localhost"
},
"storage": {
   "fs": {
     "secretString": "your_secretString"
   }
}
}

You should be able to connect ONLYOFFICE with FlinkISO once you follow these steps.

Regards
-FlinkISO Team