How to Resolve Sage 50 "Already Logged In" Error: A Practical Fix Guide That Actually Works
If you use Sage 50 regularly, chances are you've faced this message at the very least:
"Another user is already logged in" or
"Sage 50 is already logged in on this computer"

And the worst part? You have to know that no one else is online.
This isn't a sign that Sage isn't working properly. This error means Sage is thinking that a user session is active, which is usually the result of a malfunctioning closing, interruption to the network or a background process that didn't close properly.
The good news is that in most cases this issue could be fixed without reinstalling sage 50 support, https://blog.webit.ru/author/stampgas82, or calling support-- when you know what's the cause.
Let's look at it in detail.
What Does the "Already Logged In" Error Really Mean?
Sage 50 uses session and lock files to identify who's accessing the company's information. When everything is shut off completely this data is deleted in a timely manner.
The error occurs when:
Sage closes unexpectedly
The system crashes or restarts
Network connectivity drops
A user logs out incorrectly
Sage processes are still active in the background
In short, Sage believes a user session is open even when it's not.
Common Situations Where This Error Appears
You'll typically see this error in one of the following scenarios:
Sage's first Sage after a power interruption
Switching users in an shared system
Accessing Sage 50 using a multi-user setup
The same company file is opened twice
Logging in after a forced Windows update
Remote desktop sessions ending abruptly
Knowing the time it's happening helps determine what to resolve it.
Step 1: Make Sure Sage Is Fully Closed Everywhere
Before you tackle technical fixes try the obvious. However, do it in a way that is safe.
Check on the Same Computer
A restart will end hidden background processes more frequently than you'd imagine.
Check Other Computers (Multi-User Setup)
When Sage can be installed on multiple systems:
Request other users to log out
Be sure to ensure that nobody has Sage either slowed down or is in idle
Restart the server in case it is needed.
Lots of "already logged in" errors originate from closed sessions that were forgotten on a different machine.
Step 2: Close Step 2: Remove Sage Processes from Task Monitor
Sometimes Sage appears to be looking closed, but he isn't.
How to Do It
Press Ctrl + Shift + Esc
Open Task Manager
You can look for:
Select each of them, and click End Task.
Once done, reopen Sage 50.
This fix is enough to solve the issue for a significant amount of users.
Step 3: Check and Remove Temporary Lock Files
This is the most effective remedy if the error just refuses to go away.
Sage creates locking files in the company data folder.