Error 500 internal service error
I have recently begun receiving this error message each time I attempt to access a website that I have accessed successfully for years. My operating system is macOS High Sierra 10.13.6. As recommended in previous answers, I have cleared my browser history and my cache but this did not solve the problem. I get this message on both Chrome and Safari. Any help would be appreciated as this is a website I need to be able to access. BTW, I have no problem accessing it on my laptop that runs Windows.
iMac 21.5", macOS 10.13