Why do computers and laptops in the office not immediately connect to the Internet at the first start?

Question

Computer networks

In the morning, when computers and laptops are turned on, the Internet does not turn on immediately. There is a connection, but without access to the Internet. You have to restart the computer or reconnect the wire, or turn the network card on and off. And that doesn't always help. Sometimes you have to go into the settings and change things there. On laptops, you have to reconnect to Wi-Fi.
5 computers are connected via cable and about the same number of laptops via Wi-Fi.
Phones connected immediately without problems.
The organization of the network is An ordinary home router from Rostelecom. Then one cable goes to the switch, three cables go from the switch, one to the Wi-Fi point, and two wires also go to the switches. From the second switches to computers.
I built the network myself. Most likely rukozpo, because I'm not very good at it. But before that everything worked without interruptions and problems. The problems started about a couple of weeks ago. Possibly after a Windows update. Operating systems for all pirates. I tried manually assigning an IP address, it did not help. Diagnostics writes that there are some problems with dns.
Called the master. But he will come only on Sunday. And I would like to solve the problems right now. Thanks in advance. Ready to thank financially if you solve the problem.

Answer 1

Register manually DNS both in the router and on the PC 8.8.8.8 and 8.8.4.4

Answer 2

Well, until the dhcp services start, while additional services start
until the machine receives ip, dns, etc.
if the router acts as a host, then register all the settings for each machine there
, such as issuing a specific ip for a specific Mac address
On the PC, also write ip
As a dns server, again set the host
And then you can choose your own
Switches managed?
It would be nice to draw a network map with addresses

Answer 3

Here, maybe. anything - and incorrect distribution of IP addresses, and broken cables, and buggy devices. Or someone plugged the two ends of the cable into the switch.
First you need to run ping on IP addresses - from each machine, ping all the others. You may be able to see the location of the problem.
If there are problems with DNS, you need to look at which DNS server is registered in the settings: statically or from a DHCP server (ipconfig / all). And see if there is a DNS server there.
Alternatively, the router may incorrectly redirect DNS requests to an upstream server.
In such questions it is necessary to indicate the geolocation - something like "Moscow, five minutes by tram from the Kyiv metro station" (I know that there is no tram there - this is just an example).