Why ping doesn't work???
I have two computers: one laptop with Windows 7 SP1 and one PC with Windows XP SP2.
I have internet access on all computers.
If I connect computers trough routers -> ping (command prompt) doesn't work (time out)
while the ping from the router page works ok.
If I reinstall on PC with Windows XP SP2 the OS Windows 7 SP1 ping doesn't work neither - so that won't solve my problem!
If I connect the two computers with an UTP cable, I make a peer-to-peer network, I set proper IPs: result: the ping works ok.
The IP addresses from router page seems to be of all devices with was once connected, and not devices which are currently connected!
From what I saw it seems that problems come from the router!
 

Edited May 19, 20187 yr by CodeExplorer

Make sure you can send and receive ICMP messages, ping requires that.

Some routers have an AP isolation option to prevent devices from communicating with each other.
Disabling this option can solve your problem.

https://www.tp-link.com/us/faq-2089.html
https://www.linksys.com/us/support-article?articleNum=135098

I've forget some infos:

Quote

Device Information
Software Version     RP2624
Device Model     AN5506-02-FG

I tend to think that my router is a piece of crap!

@Extreme Coders: My router doesn't have that option!

I've found a strange thing:
Settings » LAN » DHCP Server
Option60 with two options Disabled or Server

 

Edited May 19, 20187 yr by CodeExplorer

DHCP is for assigning IPs to devices when they connect to the router.

Looks like this is a common problem with that brand of router.
Check this gist: https://gist.github.com/kbeflo/de3b1610b1879f8e92966ba106f83f97

Apparently, there seems to be a client isolation feature buts its hidden in the main ui.
Have to edit the html in order to display it. No idea whether it'll work or not.

 

Many thanks to all who helped me!
Now I'm sure that Isolation is the problem.
A firmware upgrade of router may be a solution, but I can't find any firmware for that device!
I would even downgrade my router firmware if that would solve my problem!
 

Receptor TBN100B - optical receiver
https://wifimag.ro/fibra-optica/receptor-optic-ftth-catv-fwr-8610gsd

I just need a router with PON slot (optical fiber)!
But I wanna repair the old one.

Edited May 19, 20187 yr by CodeExplorer

The optical receiver I have is for TV not internet!
My bad!!!
 

Edited May 19, 20187 yr by CodeExplorer