Unity projects not working Error"could not establish a connection with unity"

my unity projects start loading a little, and then stop working and gives me the error message bellow.


i’ve tried:

1 - restoring my windows 10 to previews point, didn’t work

2 - open new projects, didn’t work

3 - opening older projects with older version 2018.4.8f1, didn’t work either

i ran diagnostics, and this is the message bellow:

4 out of 6 checks passed:
    "name": "UPM registry reachable",
    "description": "Make an HTTP request to the UPM package registry",
    "result": "PASS",
    "detail": "HTTP/1.1 200 OK

X-Powered-By: Express
Provider: Genesis
Date: Mon, 20 Jan 2020 17:47:00 GMT
Connection: close"
“name”: “Ping UPM registry”,
“description”: “Measure the latency of the UPM package registry API”,
“result”: “WARNING”,
“detail”: “4 pings made in 5.143 seconds
Average latency: 213.13 ms
Minimum latency: 169.06 ms
Maximum latency: 230.32 ms
Standard deviation: 29.44”
“name”: “Ping UPM download”,
“description”: “Measure the latency of the UPM package download endpoint”,
“result”: “WARNING”,
“detail”: “3 pings made in 6.711 seconds
Average latency: 234.60 ms
Minimum latency: 224.22 ms
Maximum latency: 247.16 ms
Standard deviation: 11.62”
“name”: “UPM registry download speed”,
“description”: “Test the Internet connection using the UPM package registry”,
“result”: “PASS”,
“detail”: “Measured speed to the UPM registry: 3.18 Megabits per second”
“name”: “Speedtest.net”,
“description”: “Test the Internet connection using Speedtest.net”,
“result”: “PASS”,
“detail”: “Measured speed to the Speedtest.net server: 4.22 Megabits per second”
“name”: “HTTP proxy environment variables”,
“description”: “Detect whether proxy-related environment variables are set (HTTP_PROXY, HTTPS_PROXY, ALL_PROXY, NO_PROXY, UNITY_PROXYSERVER, UNITY_NOPROXY)”,
“result”: “PASS”,
“detail”: “No proxy support has been configured through environment variables.”

did you manage to fix the problem? I have the same mistakes