There are many reasons, but if manually connecting the shared folder using cmd, then it should work and some settings might be need to set.

To do manual cmd (as admin):

net use \\192.168.x.x /user:guest

If this works, one solution is to enable LAN Manager authentication level in the network policy:

• Open Local Security Policy (if available, press Windows + R, type secpol.msc, and press Enter).
• Navigate to Local Policies > Security Options.
• Find Network security: LAN Manager authentication level and set it to Send LM & NTLM responses.

Another is to enable guest login:

• Press Windows + R, type gpedit.msc, and press Enter.
• Go to Computer Configuration > Administrative Templates > Network > Lanman Workstation.
• Double-click on Enable insecure guest logons.
• Set it to Enabled and click Apply > OK.
• After making this change, restart your PC to apply the new settings.