For the OS I'd recommend Windows 2003 for trouble free, It'll run on a P3 800 and even period correct. We installed it on many P3 servers back when it was first released.
As the latest OS that'll probably run it benefits from the most refinement. Win2k is also a good option bit lighter on system resources and for simple file server will do the job just as well.
Both of these allow you to remote to the server. Windows 2000 predates RDP and came with a program called TS client which can run on Win3x and above.

NT4 you loose the inbuilt remote connection unless you install NT4 Terminal Server Edition. It can still act as a file server no problem though.
The most up to date versions of RDP broke compatibility with all of these OS's so you can use the TS client on modern PC's to remote in.
Win9x era RDP can remote into all 3 servers (2003/2000/NT4 Terminal server)

For the network side of things give all your PC's the same name in the workgroup field. create a user on the server and use this user to logon with all your PC's
This way it'll connect to the share immediately and not prompt for a username.

For even more fun and better results with accessing shares you can set the server up as a domain controller
If the server is on 24/7 this ensures the PC's will connect to the shares every boot but not strictly necessary 😉

chinny22 wrote on 2020-08-23, 07:46:

For the OS I'd recommend Windows 2003 for trouble free, It'll run on a P3 800 and even period correct. We installed it on many […]
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For the OS I'd recommend Windows 2003 for trouble free, It'll run on a P3 800 and even period correct. We installed it on many P3 servers back when it was first released.
As the latest OS that'll probably run it benefits from the most refinement. Win2k is also a good option bit lighter on system resources and for simple file server will do the job just as well.
Both of these allow you to remote to the server. Windows 2000 predates RDP and came with a program called TS client which can run on Win3x and above.

NT4 you loose the inbuilt remote connection unless you install NT4 Terminal Server Edition. It can still act as a file server no problem though.
The most up to date versions of RDP broke compatibility with all of these OS's so you can use the TS client on modern PC's to remote in.
Win9x era RDP can remote into all 3 servers (2003/2000/NT4 Terminal server)

For the network side of things give all your PC's the same name in the workgroup field. create a user on the server and use this user to logon with all your PC's
This way it'll connect to the share immediately and not prompt for a username.

For even more fun and better results with accessing shares you can set the server up as a domain controller
If the server is on 24/7 this ensures the PC's will connect to the shares every boot but not strictly necessary 😉

I'm leery of 2k3 only because i can't get 3.11/3.1/dos to talk to it's shares on an XP machine at all, i assume 2k3 would have the same problem. I havn't tried with 2000 yet, but i was told NT4 was problem free for setting up the shares.

XP/2003 and below all use SMB1 so should be fine. XP does have the firewall but apart from that they all act the same with simple filesharing.
I suspect the issue is not being in the same workgroup or not using the same username on the client server.

You know this is the case when Win9x or below brings up a password box, problem is is doenst let you change the username.
but if you have logged into the PC with a username also setup on the server the problem is avoided.

Having the same workgroup helps with displaying PC's in network neigbourhood but it it's not very reliable. For that you'll want to set up a domain. (Its very easy)
Otherwise going to \\IP address will always work.

Should also be said that Windows server in a workgroup just doing file shares has no benifit over NT Workstation, 2K Pro, XP apart from the remote console.
So if these arent talking to each other on the network introducing a server equivalent isnt going to change anything.

Servers are fun though 😀

I also had trouble with DOS/Win 3.1/Windows 9x and shares but that all had to do with authentication. "Newer" Windowses and Samba (Linux/BSD) don't support older authentication schemes, so if the shares requires that you log in as a certain user they won't work.

Globally accessible shares, read only or not, that don't require a password should still work.

It is probably not the approach that you want to take, but I use a Raspberry Pi with Samba for that purpose. You can easily set it to SMB1/Lan Manager authentication and it works pretty flawlessly with these old versions of Windows.

I can connect to 2003 server fileshares with my retro boxes just fine. There maybe other settings but this one is the one i can remember off the top of my head.

Main issue with 9x is the previously mentioned user account needing to be used for logon, and if you are using NTLM2 then you need to either allow NTLM and LM on your server or install the bits to allow NTLMv2. For DOS it's likely just LM. Use an 8 character password. In fact make it a very simple one when first settings things up.

If you've locked down the windows firewall or are using a 3rd party firewall make sure you are allowing ports UDP: 137,138, TCP 139 for <2000 inbound to whichever machine is serving the files.

Someone needs to load up each windows version in a VM and write a guide and a reg export. This isn't very difficult but we get too many questions so it must be. Also there's always FTP.

I use my FreeNAS server to host my files, works fine with 95+. Don't need to jump through any hoops.

If you want to be protected against wannacry type attacks then you'd be better off hosting your files from a nix machine and disabling SMB1 on all your windows machines except for the ones that need it.

From the last time I configured my FreeNAS server a couple of years ago. (FreeNAS has a GUI for changing samba settings, for Linux just edit the .conf file):

SYSTEM->TUNABLES (MIGHT NOT BE NECESSARY)
Variable: freenas.services.smb.config.server_min_protocol
Value: NT1
Type: sysctl
Comment: SMB1

SERVICES->SMB
Auxilary Parameters->
min protocol = NT1
lanman auth = Yes
client lanman auth = Yes
client plaintext auth = Yes

The above options (one may only be necessary) will allow access to Freenas from 9x clients. The below smbpasswd command will allow access to shares requiring authentication. If the below smbpasswd does not work then your only option is to setup another share and allow guest access:
Create guest share and allow guest access. Change permissions for "Everyone" to write access

From FreeNAS command prompt:

smbpasswd -a username

Use the same username on guest as on the FreeNAS host

Here is a good article with screenshots: http://www.troubleshooters.com/linux/win9x_samba.htm

Ah yes that's another possibility (bringing the conversation back to a pure Windows client/server setup)
I install the service packs but don't bother with any further updates. I can imagine one of those bumps the default up to NTLMv2 to bring in line with Vista/2008 levels.

But yeh. I think you have enough info to get started 😀
Pick the OS of your choice and see if one of your 9x PC's connects ok (as that'll be much easier to troubleshoot then dos/3x) and we can see how it goes 😀

My 9x systems work fine, 95 needs the unofficial service pack but it then connects fine, it's my dos and 3.1 system that give me hell.

Something somewhere isnt right. shouldnt need to intall any updates offical or not, to access windows shares.
Does sound like youve upgraded to NTLM2 though updates.

Have you run up a server if so?
What OS:
What updates applied:
IP address: (this should be static not DHCP)
Workgroup:
Username:

Same questions for the PC
What OS:
What updates applied:
IP address: (DHCP is fine)
Workgroup:
Username:

can each machine ping the other

That'll do for the first step.