Although for Mac HP does not officially provide certified drivers for the Laserjet 1020 printer, there is an alternative way to install it on an Apple computer. Solve your problem using the information contained in this simple guide.
Steps
Method 1 of 2: Mac OS X Snow Leopard, Lion, and Mountain Lion (10.6, 10.7, and 10.8)
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Step 1. Turn off and unplug the printer
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Step 2. Download and install the drivers from this link
Note: these are very large files and the download may take several minutes. (Reading the list of supported printer models you will notice that the HP LaserJet 1020 is not one of them. For now, don't worry.)
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Step 3. Restart your Mac
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Step 4. Turn on and connect the printer to the computer
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Step 5. Open the 'System Preferences' panel and select 'Print & Fax'
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Step 6. Press "+" to add a printer
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Step 7. Open the list of available drivers and select HP Laserjet 1022
Be careful not to select the Gutenberg version of the drivers.
Method 2 of 2: Older Macs
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Step 1. Turn off and unplug the printer
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Step 2. Download and install the latest version of HP drivers from this link
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Step 3. Open the utility panel and select 'Configure Printer', choose the HP Laserjet 1022 1.3.0.261 model
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Step 4. Download this file
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Step 5. Open the '/ Library / Receipts' folder and delete any files in it relating to the HP 1020 printer
For example 'hp LaserJet 1020 Series.pkg'.
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Step 6. Open the utilities panel and select 'Install Printer'
Delete any file related to the HP 1020 printer.
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Step 7. Run the previously downloaded DMG file
Despite its name being 'hp Laserjet 1022 Series.pkg' it will still be fine.
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Step 8. Turn on and connect the printer to the computer
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Step 9. Open the 'System Preferences' panel and select 'Print & Fax'
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Step 10. Select the HP LaserJet 1020 printer
If you cannot find it in the printer configuration panel, you may need to select the 'Browser' item and, in the dialog box that appears, choose HP1020.