Quick answers to the five questions asked most often
Most computer worries come down to a small number of situations. Here are the short versions, each linking to the longer answer.
A computer that has become slow is far more often full than infected. Storage close to capacity, a long list of programs starting with the machine, and a browser holding dozens of tabs explain the great majority of cases. The longer answer sets out how to tell the difference.
Clicking a bad link is not the same as being harmed by it. Opening a page does less than entering details into it or running a file it offered you. What you did after the click decides what to do next. Read the steps in order.
A homepage or search engine that changes on its own usually points at a browser extension or a bundled installer, not at a deep problem in the operating system. Removing the extension normally ends it. See how to find the one responsible.
If an account has been broken into, the password change comes first and the sign-out of other sessions comes immediately after. Changing the password alone can leave an intruder signed in. The full sequence is here.
Paid security software is a reasonable purchase for some households and unnecessary for others. It is not a legal requirement, and it does not replace updates, backups or care with email. The comparison starts with what you already have.
Every question answered on this site
The five topic pages below group related questions. Each answer follows the same shape: a direct answer, the causes that usually sit behind it, what to try at no cost, when to involve an official source of help, and whether a paid product changes anything.
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My computer has slowed down
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I clicked a link I should not have
- I clicked a link in a text message. What should I do now?
- I typed my details into the page before I realised. What then?
- How do I tell a fake delivery or bank message from a real one?
- I opened an attachment. How worried should I be?
- Who do I report it to in Australia?
- Someone rang claiming to be from a software company. Was that real?
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Pop-ups and browser changes
- My browser homepage changed by itself. Is that serious?
- Why am I suddenly seeing pop-ups on every site?
- Where are these desktop notifications coming from?
- A page said my computer had a problem and gave a phone number. What is that?
- I did not install this toolbar. How did it get there?
- Will resetting the browser lose my bookmarks and passwords?
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Accounts and passwords
- I think someone else has been in my account. What first?
- I was told my details appeared in a data breach. Does that matter?
- Is a password manager safer than writing passwords down?
- What does two-factor authentication actually stop?
- I used the same password everywhere. Where do I start?
- Why does everyone say to secure the email account first?
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Choosing security software
- Is the protection built into Windows enough on its own?
- Does a Mac need antivirus software?
- What does a paid licence add over a free one?
- Can I run two antivirus programs at the same time?
- What will security software not protect me from?
- My licence is about to renew at a higher price. What are my options?
Symptoms, and the cause worth checking first
A symptom rarely has one explanation, but it usually has a most likely one. This table gives the first thing to look at in each case, before anything is installed or paid for.
| What you notice | Most likely cause | First thing to check |
|---|---|---|
| Everything is slower than it was a year ago | Storage nearly full, or more programs starting with the machine than before | Free space on the system drive, and the list of startup items |
| The browser is slow but other programs are fine | Extensions, or a very large number of open tabs | The extension list, disabling them in groups |
| Pop-ups appear on sites that never had them | An extension or bundled program inserting advertisements | Recently added extensions and recently installed programs |
| Notifications arrive from a website you do not recall | Notification permission granted to a site, often by accident | The browser's notification permission list |
| The search engine or homepage is not the one you set | A setting changed by an extension or an installer | Search and startup settings, then the extension list |
| Fans run loudly with nothing open | Background updates, indexing, or dust and heat | The activity or task monitor, and the vents |
| Files have unfamiliar extensions and will not open | Possible ransomware, or a changed default program | Stop using the machine and seek help before paying anyone |
Free steps worth trying before you spend anything
These cost nothing, apply to nearly every situation on this site, and often remove the need for anything further. They are listed in the order that tends to help most.
- Restart the computer. A restart clears stuck processes and applies updates that were waiting.
- Install the operating system updates that are pending, then restart again.
- Check free space on the drive the system is installed on, and clear room if it is nearly full.
- Review the list of programs that start automatically and switch off the ones you do not need immediately.
- Look through browser extensions and remove anything you do not recognise or no longer use.
- Run a full scan with the security software already on the machine, including the one built into the operating system.
- Make a copy of files you cannot replace, onto a drive or service that is not permanently connected.
If the problem survives all seven, it is worth a careful look at hardware, at a specific program, or at help from the vendor whose product is involved. The Australian Cyber Security Centre publishes step-by-step guidance for individuals and families at cyber.gov.au.
When the problem is not the software
A surprising share of complaints that arrive as "I think I have a virus" turn out to be something else entirely. Mechanical drives slow down as they fill and fragment. Laptop batteries lose capacity and the machine reduces its own speed to cope. Dust blocks vents, temperatures rise, and the processor slows itself deliberately to avoid damage. A home internet connection shared by several video streams will make every website feel broken without a single thing being wrong with the computer.
The practical consequence is that buying software does not fix a hardware problem, and no scan will report one. If a computer is slow only when it is warm, or only when it is unplugged, or only on one network, that pattern is the answer. Noticing the pattern is usually cheaper than any purchase.
The same applies to the human side of a problem. A great deal of what goes wrong online involves persuasion rather than software: a message that imitates a bank, a telephone call that asks for access, a page that invites you to confirm details an organisation already holds. None of those are stopped by a product, and all of them become far less effective once you recognise the shape of them. That is why several of the answers here spend longer on what a message is trying to achieve than on what to install afterwards.
Where a paid product such as Norton AntiVirus Plus fits
Norton AntiVirus Plus is a commercial antivirus product for desktop computers. Whether it is worth buying depends on what you already have and how the computer is used. A household where one careful person reads email on an up-to-date machine with the built-in protection switched on is in a different position from a shared family computer used by several people, including children, with games and downloads coming from many places.
It is also worth being clear about what a product of this kind does not address. It does not recover a password you have given to a convincing fake sign-in page, it does not undo a bank transfer you authorised yourself, it does not replace backups, and it does not make an unsupported operating system supported again. Those gaps are covered on the page about what security software cannot do.
Visit the Norton AntiVirus Plus websitePaid affiliate link. Mildfactor is paid a commission if a purchase follows this link; the price you pay does not change.
Reporting a scam or harmful content in Australia
Reporting matters even when nothing was lost, because the pattern of reports is what lets agencies warn other people. Four bodies cover most situations for people in Australia.
- The Australian Cyber Security Centre takes reports of cybercrime through ReportCyber and publishes advice for individuals, at cyber.gov.au.
- Scamwatch, run by the National Anti-Scam Centre, collects reports about scams and publishes current examples, at scamwatch.gov.au.
- The eSafety Commissioner handles online abuse, image-based abuse and harmful content, at esafety.gov.au.
- The Office of the Australian Information Commissioner oversees privacy and data breach obligations, at oaic.gov.au.
If money has moved, contact your bank before anything else. Australian banks have internal processes for suspected fraudulent transfers, and speed matters more than completeness.
How these answers are written and checked
Questions are chosen from the wording people actually use when they search: ordinary sentences rather than technical terms. An answer is written only where there is a clear, general response that holds for most readers on a Windows or macOS desktop. Where the honest answer is "it depends", the page says what it depends on instead of guessing.
Each answer is checked against the published guidance of the relevant authority or vendor, and the whole set is reviewed on a fixed cycle. Mildfactor does not test products, publish benchmark figures or score vendors against one another, because it has a commercial relationship with a vendor mentioned on the site and a scoring exercise under those conditions would not be worth reading. The About page sets out the method and the relationship in full.
Terms you will meet in these answers
A few words appear repeatedly, and they are used here in their ordinary technical sense. They are defined because the same words are used loosely in advertising, where "virus" tends to stand in for every possible problem and the distinctions below are exactly the ones that decide what you should do next.
- Malware
- Any program written to act against the interests of the person using the computer. Viruses, ransomware and spyware are types of malware.
- Phishing
- A message designed to make you enter real credentials into a page the sender controls.
- Extension
- A small add-on that changes how a browser behaves. Useful ones and harmful ones install the same way.
- Two-factor authentication
- A second proof of identity beyond the password, usually a code from an app or a physical key.
- Potentially unwanted program
- Software that is not clearly malicious but was installed alongside something else and changes settings or shows advertisements.
Frequently asked questions about this site
No. Mildfactor is a set of written answers. It runs no scan, makes no assessment of your device, and has no way of knowing anything about it. Every visitor sees the same pages.
Only through paid affiliate links, which are disclosed. Mildfactor is published by BETA - CZECH, s.r.o. and is not an official site, a reseller or an authorised representative of any security vendor.
No law requires a private individual in Australia to buy security software for a home computer. Whether a paid licence is useful is a practical judgement about how the computer is used, and the free steps on this site come first.
Mildfactor publishes general answers and does not provide technical support, remote assistance or individual advice. For a problem specific to one machine, a local technician or the vendor's own support channel is the right place.