Multiple PC network struggle to stay connected

Jul 12, 2018
At our business we struggle with the PC's connected to the Main PC to stay connected.
It Keeps losing the Main PC, and then sometimes almost always struggles to load again.
We have 3 PC's that are linked with the Main PC, could it be the wifi? Even though the signal is very strong? Other devices are also connected to the wifi? All the data is on the Main PC, so that everyone can access it. Sometimes even the Main PC Struggles by throwing out an error? Should we rather get a Qualified Person to come and solve it, the last time a IT person came and just said the PC's work hard.Is that possible to explain it that way? Other days it works perfectly and then even if the weather is good and not a lot of devices are on the wifi it losing signal.
Please help!!!!