On my Acer Aspire 4720Z, running out of disk space for DATA ("D"); constantly get warnings

Msemly
Msemly Member Posts: 1 New User

ran Memory Diagnostic-showed a problem; initally said it was a hardware problem. After test finished, just said to contact computer manufacturer. OS is Windows 7,SP 1. This computer initally came with Vista. I bought an extra GB of memory when I bought it in 2/08. I upgraded to Windows 7. Recently had problem with a Windows IE (10) "virus", and Staples was able to save a few files for me, and reinstalled a full version of Windows 7, using the disk I purchased when I upgraded from Vista.  I know there are a lot of backups on Data ( "D"), some go back to Vista- have NO IDEA what to delete. I thought more recent backups were set to delete older ones.  Duplicate files have been deleted. I don't know why it's low on memory. I don't have much in the way of documents, do have some photos, and not many programs anymore. Can anyone help???