i have reset my atom to Factory Defaults by doing
rename .atom .atom-backup

then i install 2 packages atom-ide-base and ide-csharp and all their dependencies.
after that the atom prompts:

linter-ui-default needs to install dependencies
intentions
Install dependency?
i clicked yes. but it is not actually downloading.
so i searched this intentions package and downloaded it.

i get following advices from here:
steelbrain/linter-ui-default#628 (comment)

so i closed the atom and go to C:\Users\stary.atom\packages\ide-csharp\package.json and changed to
"atom-languageclient": "^1",
"omnisharp-client": "^7"
again.
run C:\Users\stary.atom\packages\ide-csharp> apm install
Installing modules done
again.
then i start the atom opened a file c.cs which content is:

namespace HelloWorld
{
class Hello {
static void Main(string[] args)
{
System.Console.WriteLine("Hello World!");
}}}}
1
2;.'.'2+3fwe
213}}}

still, no error or warning, no outlines, nothing is working.
i checked the package list again:

atom-ide-base
atom-ide-datatip
atom-ide-definitions
aton-ide-hyperclick
atom-idemarkdown-service
atom-ide-outline
atom-ide-signiture-help
busy-signal
ide-csharp
linter
linter-ui-default
intentions

the intentions is still disabled.