An offer of free anti-virus
or anti-malware software
software is essentially a marketing technique
...a way of advertising and enticement to get folks to try a product and if they like it, to purchase the full (Premium/Pro) version which typically provides more features. Marketing and promotional strategies are built into the vendor's business model as part of their operating costs. Bottom line...it's all about generating revenue and finding new and creative ways to do so
. As such, users may have to deal with occasional nagging pop-ups, nuisance advertising and prompts to upgrade to the paid version or purchase other products.By using such free programs, you are essentially agreeing to the terms of the vendor's service which includes those annoying pop-ups and ads.
In some cases you may be able to disable them through the program's settings if the vendor included an option to disable them. If the vendor does not have such an option listed, then your only alternative is to switch to another product if the pop-up and ads annoy you that much.
Also keep in mind that many anti-virus vendors are bundling toolbars and other software with their products as a cost recoup measure. In fact, all free Anti-virus programs now come with toolbars or other bundled software (and annoying ads or prompts to upgrade) except Bitdefender Free, Sophos Home, Microsoft Security Essentials and Windows 8/10 Defender
. Kaspersky Free does not have ads but does prompt users to purchase their full Internet Security suite. Bundling software combined with unnecessary features (bloatware) tends to drain system resources and slow performance.
With that said, I would recommend Kaspersky Free Antivirus
, Sophos Home Free Antivirus
, Panda Cloud Antivirus
or Bitdefender Anti-virus Free Edition
if you prefer not to use Windows 8/10 Defender
or Microsoft Security Essentials
, the free solution for Windows 7 and Vista SP1/SP2 that combines the features of an anti-virus and anti-malware scanner to provide real-time protection.