Security Basics
7 Warning Signs Your Computer Has Been Hacked — And What to Do Right Now
If something feels "off" about your computer lately — it's running slowly, strange programs have appeared, or your friends are asking about odd emails you supposedly sent — don't brush it off. These can be early warning signs that someone else has access to your machine.
The good news: catching it early makes a big difference. In most cases, you can stop the damage before your personal information, bank accounts, or identity are seriously compromised.
Here are 7 clear warning signs to watch for, plus the exact steps to take if you think something is wrong.
Sign 1: Your Computer Has Slowed Way Down — For No Reason
One of the most common signs of a hacked computer is a sudden, unexplained slowdown. If your computer used to open programs quickly and now everything drags, something may be running in the background without your knowledge.
Hackers often install programs called "malware" that silently use your computer's power — sometimes to mine cryptocurrency for them, sometimes to spy on your keystrokes, and sometimes to send spam to thousands of people using your machine.
What's normal slowness? Computers naturally get slower as they age, or when you have many browser tabs open. What's not normal is when the slowdown is sudden, happens even when you're not doing much, and is paired with other signs on this list.
Sign 2: Programs Open or Close on Their Own
Have you ever seen your mouse cursor move on its own? Or watched a program suddenly open when you didn't click anything?
This is one of the scariest signs — and unfortunately, one of the clearest. It may mean a scammer has "remote access" to your computer. This is a common trick used in tech support scams, where a criminal convinces you to let them connect to your computer to "fix a problem." Once they're in, they can see everything you type, read your saved passwords, and even transfer money from your bank accounts.
If this happens, stop using the computer immediately. Unplug it from the internet (disconnect the Wi-Fi or unplug the ethernet cable), and call a trusted family member or your local computer repair shop.
Sign 3: Your Friends or Family Say They Got Strange Emails From You
If someone contacts you to ask "Did you really send me this?" — that's a serious red flag.
Hackers who break into an email account often use it to send spam or phishing emails to everyone in your contacts. They're hoping your friends will trust a message that seems to come from you.
Signs of a compromised email account include:
- Emails in your "Sent" folder that you didn't write
- Friends or family reporting weird messages from your address
- People you know clicking a link "you sent" and their own accounts getting hacked afterward
If this happens, change your email password immediately from a different device (like your phone), and turn on two-step verification.
Sign 4: Your Passwords Stop Working
You type in the same password you always use, and suddenly it doesn't work. This can mean a hacker got into your account and changed the password to lock you out — a technique criminals use to take over accounts before stealing from them.
This is especially dangerous if it happens with:
- Your email account (because password reset links go to your email)
- Your bank or investment accounts
- Your Social Security or Medicare online accounts
If you're locked out of an account you didn't change, treat it as an emergency. Contact the company directly (use the phone number on the back of your card or a known official website — not a number that appears in a search result, which could be fake) and report that your account may have been taken over.
Sign 5: New Programs Appear That You Didn't Install
Take a look at your list of installed programs. On Windows, open the Start menu and go to Settings → Apps. On a Mac, open the Finder and click Applications.
If you see programs you don't recognize and didn't install yourself, that's worth investigating. Some are harmless — Windows or your antivirus may install updates automatically. But others could be malware placed there by a hacker or accidentally installed when you clicked a fake "Update" button on a website.
A few names to be especially suspicious of:
- Programs with generic names like "PC Optimizer Pro" or "SpeedBooster"
- Any program that appeared after you clicked a pop-up warning
- Browser "toolbars" you don't remember adding
Don't just ignore unfamiliar programs — and don't try to delete them without guidance, as some malware fights back if you try to remove it the wrong way.
Sign 6: Your Web Browser Keeps Going to Strange Websites
If you type a web address or click a link and end up somewhere completely different — especially a page full of ads, fake virus warnings, or offers that seem too good to be true — your browser may have been "hijacked."
Browser hijackers are programs that redirect your internet traffic. They're often installed accidentally through "free" software downloads or clicking fake update buttons. They can also be used to show you fake banking websites that steal your login information.
Other signs of browser hijacking:
- Your homepage changed and you didn't change it
- A new search engine appears instead of Google or Bing
- Ads pop up even on websites that normally don't have many
If you notice this, run a scan with your antivirus software immediately.
Sign 7: Your Security Software Was Turned Off
Legitimate antivirus or security programs don't turn themselves off. If you check your security software and find it's been disabled — or if you get a notification that your firewall is off and you didn't change anything — that can mean malware has specifically targeted your defenses to disable them.
Some malware is designed to "kill" antivirus programs first, so it can operate without being detected. Think of it like a burglar cutting your security camera before breaking in.
On Windows, you can check your security status by clicking the Start menu → Settings → Privacy & Security → Windows Security. Look for any yellow or red warnings.
What to Do If You See These Warning Signs
Stay calm — panicking leads to mistakes. Here's a clear, step-by-step response:
Step 1: Disconnect from the internet.
Unplug the Wi-Fi or ethernet cable. This stops a hacker from sending commands to your computer or stealing more data while you work on the problem.
Step 2: Don't try to log into accounts from that computer.
Until the computer is clean, anything you type (including passwords) could be captured.
Step 3: Run a full antivirus scan.
If you have antivirus software, run the deepest scan available. If you don't have antivirus software, see if a trusted family member can help you install a reputable option from another device.
Step 4: Change your passwords — but from a different device.
Use your phone or a family member's computer to change the passwords on your most important accounts: email first, then bank accounts, then anything else.
Step 5: Check your financial accounts for unauthorized activity.
Look for charges or transfers you didn't make. If you find anything, call your bank immediately — most banks have 24/7 fraud lines.
Step 6: Consider an identity protection service.
When a computer is hacked, personal information is often stolen and sold online. An identity monitoring service watches for your information appearing in places it shouldn't — like the dark web or in new credit applications — and alerts you immediately.
Aura Identity Protection monitors your Social Security number, bank accounts, credit reports, and passwords in real time. If something suspicious shows up — even months after a hack — Aura alerts you so you can act before the damage spreads. They also include up to $1 million in identity theft insurance if the worst happens.
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Keep your computer updated. Those update notifications that pop up? They're important. Most updates include security fixes for newly discovered weaknesses that hackers exploit. Turn on automatic updates if you can.
Use strong, unique passwords. The same password used on multiple sites is a major risk. If one site gets hacked and your password is leaked, criminals try it everywhere else. A password manager stores strong, unique passwords for every site so you don't have to remember them.
Be skeptical of unexpected phone calls, pop-ups, and emails. Real companies — Microsoft, Apple, Social Security, Medicare — don't call you out of the blue to warn you about problems. They don't send urgent pop-up messages telling you to call a number. If something feels urgent and scary, it's probably a scam designed to make you act without thinking.
A Final Word
Your computer holds a lot of your life: your email, your photos, your banking information. It's worth taking a few minutes to check for these warning signs — especially if something has felt "off" lately.
You don't need to be a tech expert to protect yourself. You just need to know what to look for and what to do when you spot it.
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Last updated: 2026-05-27