Each paid seat allows one active session. If you — or someone else using your seat — logged in on another device or browser, your original session is automatically signed out. Log back in to continue.
Why docEvault works this way
One session per seat is what makes per-seat pricing meaningful, and it means a forgotten session on a shared or public computer doesn't stay open indefinitely.
If it keeps happening
Being signed out repeatedly almost always means two people are sharing one seat. Each of you knocks the other out as you sign in, all day.
The fix is a seat per person. Seats can be added at any time and are prorated, so adding one mid-month costs only the remainder — see Plans and billing.
It can also happen if you regularly move between devices — a desktop at the office and a laptop at home, for instance. That's expected behaviour rather than a fault; you'll just need to sign in again on whichever machine you're using.
If you didn't sign in anywhere else
If you're confident nobody is sharing your seat and you're only using one device, change your password and let your admin know. See Forgot your password.