Slow printing repair
" Clear Printer Spooler Files and Enable the Spooler Service
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1. Click Start, type "Services.msc" (without the quotation marks) in the Start Search box and press Enter.
2. Double-click "Printer Spooler" in the Services list.
3. Click Stop and click OK.
4. Click Start, type "%WINDIR%\system32\spool\printers" in the Start Search box and press Enter, delete all files in this folder.
5. Click Start, type "Services.msc" (without the quotation marks) in the Start Search box and press Enter.
6. Double-click "Printer Spooler" in the Services list.
7. Click on Start. In the Startup Type list, make sure that "Automatic" is selected and click OK.
Please try the steps recommended below to uninstall printer software
Press Windows key + X, click Apps & Features or Programs and Features
Select your Brother printer.
Select Uninstall.Press Windows key + R, type control, hit Enter
Open Devices and Printers.
In the Devices and Printers window look for your Brother Printer. If you see it listed, right-click on it and choose "Delete" or "Remove Device."Open up the run command with the "Windows Key + R" key combo.
Type printui.exe /s and click OK.
Click on Drivers tab.
Look for Brother Printer driver. If you see it click on it and click Remove at the bottom.
Select OK.
Select Apply and OK on the Print Server Properties windows.
Close Devices and Printers.Proceed to reinstall the driver.