Whenever i try to open autocad i get this error "unable to initialize adlm" the body of the error goes like this "preptool has not been run since build" "error code 6"

You can fix this problem in two ways.
First: follow these steps
- Open the Registry Editor by typing "regedit" in the Windows 8 Search charm and selecting "regedit" from the Apps section of the search results.
- Navigate to the "HKEY_LOCAL_MACHINE\Software\Autodesk\AutoCAD\R15.0\ACAD-1:405\AdLM\Type" registry key.
- Right-click on the registry key and click "Export."
- Choose a name to save the license registry key file as, along with a location where you want to save it, and then click the "Save" button.
But if it useless try the second way- DWG Fix Toolbox. http://www.autocad.fixtoolbox.com/

What is the error? Are you running Norton or Mcafee virus programs? These have been known to interfere with AutoCAD (older versions).

unable to initialize adlm.internet error message:<unable to fine srecurity runtime.>Error code: <1>

http://knowledge.autodesk.com/support/autocad/troubleshooting/caas/sfdcarticles/sfdcarticles/AutoCAD-2010-does-not-start.html

Issue:

When you try to start AutoCAD, you briefly see the splash screen and the program does not start.

Solution:

This behaviour can be caused by corrupted license information.
Please check if there are any errors listed in the ACD2010ENGAdlm.log file in the folder:

C:\Documents and Settings\All Users\Application Data\Autodesk\Adlm (Windows XP)

or

C:\ProgramData\Autodesk\ADLM (Windows Vista) (Please note the file name may be slightly different for localized product versions, for example for the German version the file name is ACD2010-DEUAdlm.log)
If the log file shows errors regarding the product information table file, for example "Unable to locate the Product Information Table File" or "Product Information Table file is not found", you will need to:

1. Uninstall all installed 2010 products
2. Delete the ADLM folder mentioned above, and
3. Reinstall the products

use Autocad in windows 7 is great. vista is **** and doesnot support most of problems. i use autocad 2010 in windows 7 with no problem.......

Try rebooting your computer, then relaunch AutoCAD. If your .dwg file will not open then open the backup file. Sometimes the .dwg file goes crazy and the backup file will save your life, most of the time. Also make sure that your machine has enough memory to run AutoCAD. Memory is either your best friend or your worst enemy when working with AutoCAD. I hope this helps.