A firewall is a network security system that monitors and controls network traffic through predefined rules to protect computers or networks from unauthorized access. Its core functions include: 1. Check the source, destination address, port and protocol of the data packet; 2. Determine whether to allow connections based on trust; 3. Block suspicious or malicious behavior; 4. Support different types such as packet filtering firewalls, status detection firewalls, application layer firewalls and next-generation firewalls; 5. Users can enable built-in firewalls through operating system settings, such as Windows Security Center or macOS system preferences; 6. The firewall should be used in combination with other security measures such as strong passwords and update software to enhance protection.

System restore point setting methods include manual creation, dependency automatic creation, and management of storage space. 1. Manual creation requires system protection to enable in "Create Restore Point", allocate 5% disk space and click "Create" to name the restore point; 2. The system will automatically create restore points when installing updates or changing settings, but do not guarantee comprehensiveness; 3. The restore point occupies no more than 5% of the system disk space by default, and the old version will be automatically cleaned, and storage can be managed by adjusting the upper limit.

If you want to remotely turn off the router Wi-Fi, you must first confirm whether the router supports remote management; if it does not support it, it can be achieved through a smart socket power outage; advanced users can also consider flashing in custom firmware. The specific steps are as follows: 1. Check whether the router has remote management functions, such as the manufacturer's supporting app or cloud management functions; 2. If it is not supported, purchase and set up a smart socket and remotely cut off power through its app; 3. For technical users, you can install firmware such as DD-WRT or OpenWRT to obtain remote control permissions. Different methods have their own advantages and disadvantages. Please weigh them according to your own needs when choosing.

When encountering the blue screen error VIDEO_TDR_FAILURE(nvlddmkm.sys), priority should be given to troubleshooting graphics card driver or hardware problems. 1. Update or rollback the graphics card driver: automatically search and update through the device manager, manually install or roll back to the old stable driver using NVIDIA official website tools; 2. Adjust the TDR mechanism: Modify the TdrDelay value in the registry to extend the system waiting time; 3. Check the graphics card hardware status: monitor the temperature, power supply, interface connection and memory module; 4. Check system interference factors: run sfc/scannow to repair system files, uninstall conflicting software, and try safe mode startup to confirm the root cause of the problem. In most cases, the driver problem is first handled. If it occurs repeatedly, it needs to be further deepened.

To prevent specific programs from being connected to the network can be achieved through system firewalls or third-party tools. 1. Windows users can use their own firewall, create new rules in the "outbound rules" to select the program path and set "block connection"; 2. Third-party tools such as GlassWire or NetBalancer provide graphical interfaces that are more convenient to operate, but pay attention to source reliability and performance impact; 3. Mac users can control networking permissions through the command line with pfctl or using LittleSnitch and other tools; 4. A more thorough way is to use the network outage policy. The whitelisting policy prohibits all programs from being connected to the network by default and only allows trusted programs to access. Although the operation modes of different systems are different, the core logic is consistent, and attention should be paid to the details of the path and scope of the rules taking effect.

First, confirm the high CPU occupancy process, open the task manager to view the "CPU" tab; secondly, search the process name to determine whether it is a system or a third-party program; try to end non-critical processes, close unnecessary browser tags or plug-ins; update drivers and system patches; close unnecessary startup items; use professional tools to further analyze. The above steps can usually effectively solve the problem of computer lag.

UAC frequently pops up because the running program requires administrator permissions or the system setting level is too high. Common reasons include installation of software, modifying system settings, running third-party tools and other operation triggers. If using an administrator account, UAC only confirms the operation and not blocks. The methods for reducing prompts include: canceling the program to run as an administrator, lowering the UAC notification level, using a standard user account, and starting the program through the task planner. It is not recommended to turn off UAC completely because it can effectively prevent malicious programs from tampering with the system. You can set the UAC to "notify only when the program changes the computer" to balance security and experience.

The Facebook name change process is simple, but you need to pay attention to the rules. First, log in to the application or web version and go to "Settings and Privacy" > "Settings" > "Personal Information" > "Name", enter a new name, and save it; secondly, you must use your real name, it cannot be modified frequently within 60 days, it cannot contain special characters or numbers, and it cannot be impersonated by others, and the review does not pass the auxiliary verification such as uploading ID cards; it usually takes effect within a few minutes to 3 working days after submission; finally, the name change will not notify friends, the homepage name will be updated simultaneously, and the old name will still be displayed in the history record.