Let me guess - you're trying to access the share from Nautilus? If that's the case then the problem is Gnome lacks the ability to store username/password credentials for samba shares (which would allow you to write). You can however browse shares as read-only in the GUI. KDE sort-of works, and can store usernames and passwords which allows you to copy files to shares but in my experience it's buggy and I've had problems with deleting files.
If you're ok with read-only access then try adding "guest ok", like so:
comment = Home Directories
path = /bacups/database
invalid users = nobody
read only = No
hosts allow = 200.168.1.
guest ok = Yes
and it should work for read-only. The most stable solution I've found so far is to simply mount the share at the CLI:
mount.smbfs //<IP Address>/path/of/share /path/for/mountpoint -o username=<username>,password=<pass>,uid=1000,mask=000
But it's annoying to do this every time, so you can look into mounting the samba share through /etc/fstab. I don't do this myself so unfortunately I don't have an example readily available.