Re: Fwd: BUG?!: Running cygserver switches egid/primary group to 4095(CurrentSession)

Hello Lionel,

On 7/29/2026 12:35 AM, Lionel Cons via Cygwin wrote:
> On Fri, 12 Jun 2026 at 17:19, Lionel Cons <[email protected]> wrote:
>>
>> On Thu, 11 Jun 2026 at 11:44, Mark Geisert via Cygwin <[email protected]> wrote:
>>>
>>> Hello Lionel,
>>>
>>> On 6/8/2026 3:35 PM, Lionel Cons via Cygwin wrote:
>>> [...]
>>>> If I run without cygserver id -a returns
>>>> $ id -a
>>>> uid=197620(lcons) gid=197121(Kein)
>>>> groups=197121(Kein),197615(docker-users),545(Benutzer),559(Leistungsprotokollbenutzer),4(INTERAKTIV),66049(KONSOLENANMELDUNG),11(Authentifizierte
>>>> Benutzer),15(Diese Organisation),113(Lokales
>>>> Konto),4095(CurrentSession),66048(LOKAL),262154(NTLM-Authentifizierung),401408(Mittlere
>>>> Verbindlichkeitsstufe)
>>>>
>>>> but if I start cygserver each new session has gid=4095(CurrentSession)
>>>> as egid/primary group for new terminals
>>>> $ id -a
>>>> uid=197620(lcons) gid=4095(CurrentSession)
>>>> groups=4095(CurrentSession),197121(Kein),197615(docker-users),545(Benutzer),559(Leistungsprotokollbenutzer),4(INTERAKTIV),66049(KONSOLENANMELDUNG),11(Authentifizierte
>>>> Benutzer),15(Diese Organisation),113(Lokales
>>>> Konto),66048(LOKAL),262154(NTLM-Authentifizierung),401408(Mittlere
>>>> Verbindlichkeitsstufe)
>>>
>>> I'm unable to reproduce the issue, but I'm a little unsure I have the
>>> complete list of steps to do so.  Let's start with these questions:
>>>
>>> Is your system part of a Windows domain?
>>
>> No, this is a test installation, Windows 10, standalone, IPv4-only
>>
>>>
>>> How exactly are you starting cygserver?
>>
>> Enabled it as service with autostart, reboot.
>>
>>>
>>> When you say "each new session" do you mean opening a new Cygwin
>>> Terminal that presents the usual bash+mintty user CLI?  Or is it some
>>> other method?
>>
>> Yes, just start a new mintty process each time, and not one mintty
>> process sharing multiple windows.
> 
> Has anyone figured out a fix for this?

It appears nobody else has even seen the issue and/or reproduced it. 
Those are the first steps towards fixing it.

My go-to resource for cygserver answers has been out of commission for a 
while and will not soon return.  I have no further ideas at the moment.

..mark

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