Hello Tony,
I think I have no other way out. I am installing Clearos 7 and configuring that as a file server with windows networking(Samba) app.

Looking at that screen shot, am of the opinion that webconfig is the victim and not the root cause...
we see "zend mm heap corrupted" errors several times
""zend_mm_heap corrupted" indicates a problem with memory management often associated with some php code and/or a cache such as opcode, the end result being that apache seg faults (webconfig is really renamed apache with added scripts for the webconfig admin pages).

as for what is causing it - too many options :-
hardware - memory errors or corrupted file system on disk
a php program exhausting php's memory limit - e.g. Horde and an email with very large attachment
incompatible or badly written code (php) added to the system e.g. an rpm meant for a different distribution. Some people installed a web accelerator that was actually a fedora rpm.

Solution? As Nick indicated you have no support, no security updates, no bug updates, nothing. Never seen this problem reported here on ClearOS before throughout the history of versions 5.0 - 5.2, and your system is vulnerable...
Recommend you use this problem as a reason and opportunity to upgrade...

I was going to say that I think this is one for the devs, unless you have been tinkering with the Apache installation, but 5.1 is way out of life. 5.2 went out of life at the beginning of this year or the end of last year, so I don't think you'll get any support on 5.1.

Hello Nick,
These are the webconfig logs generated at the time of login into the webconfiguration. I am using Clearos 5.1 version

Which version of ClearOS and what are you seeing in your logs (under /var/log)?

Hello Nick,
Thank you for your reply. I restarted the webconfig service multiple times. I also rebooted the server multiple times. Still it is not working.

Hello Nick,
Thank you for your reply. I did that a multiple times and rebooted the server a lot of times but still it is not working.

From PuTTy, can you try a:

service webconfig restart