You mean Trainose? They should be part of Interrail. 

Greek railways accept Interrail but there are currently no international trains from/to Greece. Maybe that's what they meant?

I know that's what i told them

Whatever the reason might be, i want to know if there are any other contracting countries with similar straits.

No, nothing similar known. 

@Nanja  Can you please check if this is true, that Trainose doesn’t accept Interrail? Or they don’t sell it more?

@Angelo  Nanja is currently in her Holidays Currently Persons to tag are @Leo@Felipe.iturrieta  :D

@Giwrgos siamantouras  TrainOse is still part of Interrail/Eurail but they have currently no International Rail connections. There are regions for example Poland where currently many regional services are transfered to Railcompanies owned by the district goverment and because of that they are currently no part of Interrail/Eurail but the mainlines are covered in Poland :D
There are still some traincompanies that are not covered but with Interrail you have a valid ticket for more of 90% of the trains in Europe (you may need a reservation on top of Interail for example in Italy,France,Spain)

Greek Rail (Trainose) is currently a small mess as of 2016 Trenitalia (Italian Rail) took over Trainose.
Means they are now a subsidiary of Trenitalia Because of that many things changed and even some ticket offices are no sold to private operators Means they still use the Trainose Brand but are now a “normal Travelagency” :/
Had 2 years ago similar problems with a other offer in Greece but finally managed it.

So does anyone has the list with the train companies that are not covered by interail? Plus two other matters i want clarification for are : 1)  the differencies between Eurail and Interail passes 2) the duration of a traveling day while using the pass ( e.g if i travel between 20:00 (29/1)-04:00 (30/1) will it count for 1 or 2 days? 

Thank you a lot guys you’re being really helpfull 

There is a list of companies that Interrail covers. More details sometimes on the individual country pages.

The difference between Interrail and Eurail is that Eurail is for people who don't live in Europe and Interrail has limited possibilities to travel in your country of residence.

A travel day last from 0:00 until 23:59, You don't need a new travel day if you do not change trains after midnight.

You see that most questions are answered on the Interrail website.

No, there is NO list of NON-allowed trains, but as said there is poer country a list of what IS allowed.

In about half of the 33 participating countries there is just still the national burocratic state railway-like even in GR.

In some countries where they have privatised/given out to tender the rails/trains, even still all trains are allower: NO, UK, NL

But as Seewulf explains- IN PL, CZ, RO there are now many local railways that have chosen to opt out of the pass-system.

In general the new private Hi-Speed competetion is NOT allowed; Italo in IT, AVLO and QuiGO in ES, OUiGO in FR (but this is in fact owned by state-SNCF), FLIXtrain in DE (not that fast) and MTR in SE.

Also OUT of use are in some countries many of the purely local/regional companies. But f.e. in CH these are nearly all in the national system. But these lines have always been out of the system.

However, as most IR-newbees tend to use only a few well-defined direct trains between capitals and are apparently too afraid to venture out of that, the limitations are in practice not that great.

Hi @Angelo, sorry for the delay in answering. Rvdborgt and Seewulf are right, Trainose is still part of Eurail/Interrail but there are currently no international trains from/to Greece. Cheers,