The following are some tricks that criminals may use to pretend to be maintenance personnel to steal office computer equipment： **Identity disguise** 1. Forged maintenance company documents: make seemingly formal maintenance company work permits, business cards, etc., printed with false company names, contact details, and identity information of maintenance personnel, so that the victims mistakenly think they are regular maintenance personnel. 2. Wear similar overalls: wear overalls similar to regular maintenance personnel, and some may have some seemingly professional tool kits to confuse the eyes and increase credibility. **Fabricated excuses** 1. False claim of system failure: It is claimed that the computer system in the office building has a general failure, such as infection with viruses, slow operation, etc., and needs to be thoroughly inspected and repaired in order to obtain access to various offices to operate computers. Opportunity. 2. Use of emergencies: Create the illusion of an emergency, such as saying that the computer of an important department is about to affect the operation of the business and is in urgent need of maintenance, so that the staff has no time to delve into it and let it enter the maintenance as soon as possible. 3. Fraudulent use of repair information: obtain the repair records of some computers in the office building in advance (internal information may be obtained through illegal means or records left during previous normal repairs), and then request to enter the corresponding area to repair the computer on the grounds of following up on the repair, but in fact look for opportunities to steal equipment. **Means of operation** 1. Deliberately delay maintenance: During the maintenance process, deliberately create maintenance difficulties through some technical means to extend the maintenance time so that there is more time to find stolen computer equipment or its stored data, and observe the activity patterns and security conditions of personnel in the office building. 2. Replacement of hardware parts: When repairing a computer, secretly remove some important hardware parts of the computer, such as hard disks and memory sticks, while people are not paying attention, and hide them in tool kits or other hidden places to take away. These parts can be sold separately for profit. 3. Implant malicious software: Install malicious software on the computer under the pretext of detecting system problems or upgrading software. These software can steal sensitive information in the computer, such as account passwords, business confidential documents, etc., and then look for opportunities to remotely control computer equipment for data theft or other illegal activities, and the identity of the maintenance personnel is onlyIt is close to the cover of the computer.