Can't make samba share writable

I'm trying to make my samba share (running on Debian 10) writable but it seems that anything I try just breaks the share and I cannot access it anymore. Here's my current configuration: [MediaServer4TB] comment = Media Server 4TB browseable = yes path = /media/sf_filesrvr guest ok = no read only = no create mask = 0600 directory mask = 0700 security = user encrypt passwords = yes force user = root writeable = yes The client is an Ubuntu 20.04 LTS machine. Could the issue be that the machine is a virtual machine using a virtual folder as directory for the share? If yes, how would you proceed? **EDIT: I realized I can copy files and folders from the remote machine but I cannot move files inside the samba share. The directory /media/sf_filesrvr is writable by root (the user that is trying to access it)** Here is the log output for the specific client: [2022/05/01 15:33:49.864251, 3] ../../auth/ntlmssp/ntlmssp_sign.c:623(ntlmssp_sign_reset) NTLMSSP Sign/Seal - Initialising with flags: [2022/05/01 15:33:49.864280, 3] ../../auth/ntlmssp/ntlmssp_util.c:72(debug_ntlmssp_flags) Got NTLMSSP neg_flags=0x62088215 [2022/05/01 15:33:49.864331, 3] ../../auth/ntlmssp/ntlmssp_sign.c:623(ntlmssp_sign_reset) NTLMSSP Sign/Seal - Initialising with flags: [2022/05/01 15:33:49.864352, 3] ../../auth/ntlmssp/ntlmssp_util.c:72(debug_ntlmssp_flags) Got NTLMSSP neg_flags=0x62088215 [2022/05/01 15:33:49.864612, 3] ../../source3/auth/token_util.c:688(finalize_local_nt_token) Failed to fetch domain sid for WORKGROUP [2022/05/01 15:33:49.865078, 3] ../../source3/groupdb/mapping.c:854(pdb_create_builtin_alias) pdb_create_builtin_alias: Could not get a gid out of winbind [2022/05/01 15:33:49.865115, 2] ../../source3/auth/token_util.c:719(finalize_local_nt_token) WARNING: Failed to create BUILTIN\Administrators group! Can Winbind allocate gids? [2022/05/01 15:33:49.865611, 3] ../../source3/groupdb/mapping.c:854(pdb_create_builtin_alias) pdb_create_builtin_alias: Could not get a gid out of winbind [2022/05/01 15:33:49.865647, 2] ../../source3/auth/token_util.c:739(finalize_local_nt_token) WARNING: Failed to create BUILTIN\Users group! Can Winbind allocate gids? [2022/05/01 15:33:49.866176, 3] ../../source3/groupdb/mapping.c:854(pdb_create_builtin_alias) pdb_create_builtin_alias: Could not get a gid out of winbind [2022/05/01 15:33:50.008196, 3] ../../source3/smbd/password.c:84(register_homes_share) Adding homes service for user 'root' using home directory: '/root'