1.laserjet30 15 is directly connected to the computer of xp system through usb cable. If there is a question mark or exclamation mark device about this printer in the device manager, it means that there is something wrong with the communication between the printer and the computer. Communication is usually related to the data line and two interfaces connecting the data line. You can try right-clicking the question mark device and updating the drive port again. If the driver port cannot be updated, it is recommended to replace other usb ports of the computer and reconnect the data cable. If there is a new hardware installation wizard prompt or a device identification prompt, first install the usb or dot4 print port according to the prompt. If it fails, communication problems with xp system computers will not be ruled out.

Under normal circumstances, the computer of win7 system will automatically detect that the device is installed with the laserjet30 15 driver that comes with win7 system. However, when testing printers, xp system computers will generally prompt a new hardware installation wizard, and you need to install usb or dot4 printer ports according to the prompts of the wizard.

2.dot4 is a virtual print port. If you run the CD in xp system and install the driver, a virtual dot4 print port will usually be generated. If you want to select a usb port, you can update it through the dot4 port in the device manager.

3. If the printer is directly connected to the xp system computer through usb cable, the driver can be installed by adding a printer on the premise that the computer terminal is equipped with a port. The method is as follows:

Open the control panel-Printers, select Add Printer, click Next, select Add Local Printer (turn off the function of "automatically detecting and installing plug-and-play printers"), select usb or DOT4 from the following ports, click Install from Disk, then click Browse, select the downloaded and unzipped folder, and select *. Inf file, click OK, then click Next, and follow the prompts to install it (if not possible).

If official website downloaded the drivers, they are all there. Exe format, need to decompress and install. Any file you can choose. Inf type.

I hope the above reply can help you.