You were right! i double checked the folders and it told me my drive was offline. then i physically walked over to the drive bay and it was off. i turned everything on and reconnected and now everything work!
I recently made a RasPi Plex server with OMV5. Everything works except i cannot transfer files to the external drive. When i use SMB/CIFS it connects to the SD card of the RasPi instead of the External Drive.
I have shared the proper folders with guest access allowed, with no luck.
I must add that after i installed raspbian on the sd card, i used the expand drive function (?) to expand the sd card to use all the space available. Would this be the issue?