Viruses and Trojans

Information page for Trojans and virus infections on your computer, smartphone, or tablet.

For more information, see Viruses and Trojans in the Enterprise, and the topic Ransomware.

Scan for Viruses and Trojans

If you think you have a virus or Trojan, start by updating your anti-virus software and then doing a full scan of your system, network, and the external hard drives. If the anti-virus product cannot be updated, then the probability is high that you already have a virus or Trojan.

In this case, you should fall back on the Botfrei EU-Cleaner. These special programs serve as a first line of help for the detection of viruses and Trojans and can be used in parallel to anti-virus software.

You can manually upload individual files and websites to websites like Virustotal, and have them analyzed by numerous anti-virus software programs. If your anti-virus software does not, despite this, find any malware, but you are still suspicious, then you should regularly repeat the full system scan with the most recent updates.

Disconnect the device from the network

If your anti-virus software reports a find, stay calm and firstly save your data.

After you have had a report of a finding, disconnect your computer from the Internet, from your network, and from external devices. This can prevent the malware from being further distributed to other devices.

You should also avoid re-starting or rebooting the infected device.

Instead, put your computer into standby.

Ascertain damage

If you have diagnosed a Banking Trojan infection, you should use a second device to check whether there have already been any irregularities on your account, and you should also immediately change your password for online banking.

Alternatively, you can call your bank to request that the account be blocked. This is possible around the clock using the German national emergency number for blocking cards and accounts: 116 116.

Further information about accessibility from abroad: Website of the emergency blocking number service.

Alongside online banking, other payment services like PayPal are the target of criminals; here also, you should check your account and perhaps change your password.

Change passwords

After a virus infection, change all of your critical passwords, e.g. for your online banking, email addresses, social networks, and online shops.

Our tips for strong passwords.

Report damage

If a virus or Trojan has caused any damage, you should immediately report it to the police.

In this case, do not make any independent attempt to remove the malware. This is the only way it is possible for the police to secure evidence and begin an enquiry.

Use a safe second device to file a police report online .

If it is not possible to use a separate device, you should go personally to the nearest police station to make your report. Take the infected device with you to the police station to secure evidence.

Clean the computer or install backup?

After an infection with a virus or Trojan, we recommend you restore a backup, especially if you want to continue using the device for business purposes or online banking.

Unfortunately, it cannot be guaranteed that the anti-virus software will remove 100% of the malware.
If you do not have a backup, we recommend a complete new installation. Of course you should save and secure your data beforehand.

After a new installation or restoring a backup, you should examine your computer again intensively with anti-virus software. This is particularly the case for data that you saved after the infection and now wish to use again on the new system.

Help and support in the removal of malware or the reinstallation after a malware infection can be found in the Botfrei forum.

Help and support for removal

Most anti-virus software removes viruses and Trojan automatically, or offers quite detailed instructions for manual removal of malware via links.

If you nonetheless have difficulties in the removal of malware, you can get help and support free of charge from the Botfrei Community in the Botfrei forum.