That’s so important I’ll say it again - Backup your files!!!
Determine if it is Computer/OS related:
Copy the whole project to another computer. Does the project behave okay there? If not, then the problem is likely inside your project or Katalon itself.
Determine if it is the project:
Start a new project. Does Katalon behave okay now? If so, it’s your project. If not it’s Katalon. (You could backup your projects and re-download Katalon and install again)
If it is the Project…
Start deleting profiles. Check Katalon after each deletion.
Let us know WHICH profile when it was deleted allowed Katalon to work correctly. @devalex88 will want to see it (and you still have a copy because you made backups, right? )
In practical terms, 8GB of RAM is a little on the low-side for Win10 w/ Katalon. However, I do run my suites on the exact same setup without issue.
Just for reference, I use Win7 with 16GB RAM for Test Case development.
Did you try creating a new project on both computers? Did they both have the same issue?
One other question: On what version of Katalon did this problem first appear? I am wondering if it is worth trying an older version to see if the issue suddenly disappears (but not yet, let’s allow @devalex88 take a look at the rest of this thread first).
Empty it out. Write a simple test. What happens now?
A while ago (back when Win10 was new), I moved a development system (node.js and NW.js) to a shiny new Win10 system. The whole thing behaved exactly as you described. On Win7 it worked perfectly. When I blocked WinDefender from accessing everything in the dev environment (including Visual Studio and the publish folders) suddenly it started working correctly.
How are the permissions set on your project folder?
Is your user account local? Or does it come from a domain controller?
Are you opening Katalon with the same user account?