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Fatal error Class 'os' not found


I have a new installation of testRail.
On Amazon linux distro. PHP 5.5
I’ve followed the installation document. Created the host, mysql, ioncube… etc.
When I try to open the site it comes back with a 500 error.
In the log file I can see:
“Fatal error: Class ‘os’ not found in index.php on line 59”


Hello Marin,

Thanks for your posting! This is a small issue with one of the detection routines for the requirements that are checked when TestRail is loaded (the detection routine will be fixed with the upcoming 5.2 release). The underlying issue is that your PHP environment doesn’t have support for the mbstring PHP extension and this is a required PHP extension for TestRail.

For Amazon Linux, you should be able to install the mbstring PHP extension as follows:

yum install php55-mbstring

(you may need to restart Apache afterwards)

I hope this helps!



Thanks for the quick response.
This fixed the problem.


Awesome, and thanks for the confirmation :slightly_smiling: