browser is not reflecting changes, wordpress installed. Can you please help?

["XalMan.!" <sul_man21@xxxxxxxxx>]

Hi all PHPExperts,

I have strange problem. For a project we are using following cloud hosting.
http://www.rackspace.com
I have installed wordpress on four sub-domains on this server.
Now i am facing a strange problem. Sometimes when i make changes in theme flies, browser does not reflect those changes.
Like in abc.php file i have included xyz.php file. I made some changes to xyz.php but when i open that page in browser, i can not see changes. The issue is more worst, because even i tried to delete/rename xyz.php but i can still see previous include on abc.php page.
It was happening before, but after some time behaviour was normal. Now its been 2 weeks and i am facing this problem. I have contact hosting supprt, but they do not accept any issue. They say there is some issue in your wordpress. I am sure that i do not have any cache plugin in wordpress. Can you help me how to resolve this issue?

Kind Regards,
Salman Aslam

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