You can do the following to completely erase the hard drive, if that is what your business network wants.
1. Make a full back up of your hard drive. You will need an external drive and an app like Carbon Copy Cloner - make sure you download the correct version for your OS. (You can get a free 30 day trial.)
2. Boot your computer from the OS disk.
3. Select install, and instruct the installer to do a clean install.
Once again, this will completely wipe the computer's hard drive, and leave you with a fully functional Mac without any apps other than what comes with the OS.
clean scan report
What do you mean by this? What results are you looking for? List some of the results you would see in the report.
Are you saying you want to check the hd for problems?
Verify a disk
As an alternative, you can verify that the filesystem on the disk is correct. You will not be able to repair the file system.
I suggest that you use disk utility to verify that your startup disk is OK.
Macintosh-HD -> Applications -> Utilities -> Disk Utility
Start up disk utility. On the left pane view, you will see a list of all your disks.
Click on your startup disk.
Click on the First Aid Tab.
Click on verify.
Hopefully your disk will verify. If not, you have to boot from your installation DVD and run Disk Utility from there to attempt to repair your file-system.