Cant login to admin after changing domain to a subdomain

[ragnabt]

Hi

 

I have a webshop running on 1.4.7 and now I´ve created a new one 1.6.0.14 which is running on a subdomain to the main site.

 

Now I´m ready to "upgrade" my store, meaning that I want to make my old one (ver. 1.4) run on a subdomain xxxx.yyyyy.zz and then the new one on the main domain. 

 

Everything is easy peasy, but when I change the domain on the old verstion to be subdomain.maindomain.dk then I cant login to the backend. 

 

I´ve crawled the web for 2 days now for answers and I can see that i´m not the only one. I´ve followed every instruction but nothing seems to work for me. I just can´t login. 

 

the admin always redirects to the login again. Sometimes with the message that the user does not exist or pwd is wrong. 

 

When I try to visit the frontend it redirects to subdomain.maindomain.dk/subdomainfolder/  and displays an error page 404. 

 

there is no problem changing it back and the old shop works again. 

 

 

It cant be true that this is supposed to be so difficult!!!!

 

So I hope I can get help from here

 

Best regards

Ragna

Edited August 6, 2015 by ragnabt (see edit history)