If you stuck to delete the print jobs, the alternate way is through commands.
Here we will use just simple commands like net, cd and del.
Step 1: - To stop the printer spooler - from command prompt - net stop spooler
Step 2:- To entering the printer directory - from command prompt - cd \windows\system32\spool\printers
Step 3:- Delete the .shd extension files - from command prompt - del *.shd
Step 4:- Delete the .spl extension files - from command prompt - del *.spl
Step 5:- Finally start the printer spooler - from command prompt - net start spooler
Now check the printer tray icon and refresh it.