How to Deny Access to the Local Administrator on Windows 2000
Note: Before you follow these steps, make sure that there is at least one other local or network user who can gain access to the computer with administrator permissions.
1. Log on as Administrator, or as a user with administrator permissions.
2. Clicking Start, point to Programs, point to Administrative Tools, and then click Local Security Policy.
3. In the left pane, expand the Local Policies node, and then click User Rights Assignment.
4. In the right pane, double-click Deny access to this computer from the network.
5. In Local Security Policy Setting, click Add.
6. In the Users and Groups box, click the Administrator account, and then click Add.
7. Click OK, click OK, and then quit the Local Security Settings console. You must restart your computer for the new security setting to take effect.