provided by Star2Billing S.L.

I have successfully installed a2billing..
Now when login as user: 'root' and password:changepassword, I redirect to the admin page, where i see a side-list of options like CUSTOMERS, AGENTS, ADMIN etc.. Fine

Now the problem is that when i click any of the sub-menu of CUSTOMERS or AGENTS or any other, i suddenly redirect to the page where the following sentence is written:

ERROR PAGE
Sorry, you don't have access to this page !

so please tell me what to do to resolve this problem.

Either
1. your hard drive is full.
or
2. Your ownership or permissions on /var/lib/php/session/ are incorrect
or
3. You've not done the install right.

Great!
Done it.
Ya the problem was with /var/lib/php/session/.

I have corrected it.
Thanks