The Second Byte New & Used Computers

I have taken 4 different computers here and they have all come back either not fixed or with applications no longer installed that were previously there and did not need to be corrected. Example, I took my laptop in 2 weeks ago to have the IE icon uninstalled and reinstalled as it was corrupted. The computer returned over a week a later with a version that was not previously on the computer and it did not support the internet sites, including my email on Yahoo, on which I visit. I took it back, retrieved it 5 days later and my iTunes icon did not work and had to be downloaded again and Microsoft Office is gone! They are awful, slow and lazy!