There are many reasons for a sluggish PC and most of them are due to a lack of regular maintenance.
Below is a list of 5 common problems that slow a PC down:
Cluttered Registry. (Ccleaner)
Too many start up programs.
Full Hard Drive.
Not enough Memory.
Spyware & Malicious Programs. (malwarebytes)
Try’ CCleaner’. You can select what kinds of files to look for prior to scanning then select the files you want to delete. CCleaner can also erase unallocated space on the hard drive. It is called ‘wipe free space’, and this feature will help to speed up your PC.
Another good programme is ‘Defraggler’. It performs disk defragmentation. If your hard drive contains a lot of fragmented files, the program can take some time too run, but it is worth the wait.
If you can’t download any programmes – You can use what is on your PC such as ‘Disk Cleanup’, set your browser to delete history and cookies etc on closing, defrag regularly.