Did you come across with these errors during ModernBill installation??
* You MAY have the “sysvshm” extension loaded for Unix performance optimizations [you do not].
* You MAY have the “sysvsem” extension loaded for Unix performance optimizations [you do not].
Solution,
Support for sysvshm and sysvsem functions are not enabled by default. To enable System V semaphore support recompile PHP with the option –enable-sysvsem. To enable the System V shared memory support recompile PHP with the option –enable-sysvshm.
As always take the backups of important conf files before trying anthing new
Thanks