After server migration unable to login

[pushpendra]

Hi, 

I am migrating my website to a different server after content migration site is working but I am unable to login as an Admin and member. My present live website the fileserver is on the same server but on the new infrastructure I am trying to use the seperate fileserver mounted with the same name uploads. This is the only change we made. Everything is working fine except Admin and member login. I tried to ask Invision Support and they need ftp access but the site is accessible through the VPN only so this would not work.

Could you help me on this? Possible reasons will help too.

Adding screenshot of admin and member login errors