Samba share folder cant access on windows: ask your administrator for permission

I have created a shared folder in Ubuntu and made 2 users i gave all the permissions in smb.cfg . My windows machine can find the shared folder when i double click it it asks for credentials and on the bottom left it says access denied. i use my credentials and the a pop up message says that i have to ask my network administrator for permission. also i open 445 port on windows firewall and active all inbound and outbound that are smb related please advise.

The incomplete output of testparm is this:

[Personal] 
comment = "My Samba File Server" 
path = /share_folder 
read list = usermarios 
valid users = usermarios usernatali 
write list = usermarios

The usershares are this:

[Personal] 
path=/home/morfeas/Desktop/Personal 
comment= 
usershare_acl=Everyone:F, guest_ok=y 

[windows_share] 
path=/home/morfeas/windows_share 
comment= 
usershare_acl=Everyone:F, guest_ok=y
 
[shared_folder] 
path=/home/morfeas/shared_folder 
comment= 
usershare_acl=Everyone:F, guest_ok=n

The [Personal] share you defined in smb.conf makes little sense to me since usernatali can neither read or write to the share. It's basically a share for usermarios only.

The second problem is that you have 2 [Personal] shares: One in smb.conf and the other is a usershare. They are pointing to two different folders and have dissimilar permissions defined. Choose one or the other or rename one.

The third problem is all of your userhsares ar in your home folder and if you are using Ubuntu 22.04 or later guest access is impossible by default. The path=/home/morfeas/shared_folder share can work but it is by default only accessible to morfeas.

If you are in a hurry I would:

[1] Remove the share in /etc/samba/smb.conf.

[2] Right under the workgroup = WORKGROUP line in smb.conf add this one:

force user = morfeas

THen restart smbd: sudo service smbd restart