1. Genstart din computer

Sometimes problems can be fixed by simply restarting your computer and then starting Firefox again.

2. Slet dine cookies og cache

Many problems with loading web pages can be resolved by clearing Firefox's cookies and cache:

1. Klik på menuknappen Billedet "fx57menu" findes ikke. for at åbne menuen.
2. Klik på Historik, og klik så på Ryd seneste historik…
3. Klik på rullemenuen ud for Fjern, og vælg hele min historik.
4. Sæt flueben ud for både Cookies og Cache under Historik. Sørg for, at andre elementer, du vil beholde, ikke er valgt.
5. Klik på knappen OKRyd nu.

3. Genstart Firefox i fejlsikret tilstand

Fejlsikret tilstand is a troubleshooting mode that disables all extensions, uses the default theme, turns off hardware acceleration, and uses default toolbar settings and controls, among other things. To start Firefox in Safe Mode:

1. Klik på menuknappen . Klik på Hjælp, og klik så på Fejlsøgnings-tilstand…. Klik på knappen Genstart i vinduet Genstart Firefox i fejlsøgnings-tilstand?

   Bemærk: Du kan også starte Firefox i fejlsøgnings-tilstand ved at holde tasten Skift nede, mens Firefox startes. holde tasten Alternativ nede, mens Firefox startes. afslutte Firefox og i Terminal starte Firefox med kommandoen firefox -safe-mode
   Du kan være nødt til at angive stien til Firefox-installationen (fx /usr/lib/firefox)
2. In the Firefox Safe Mode dialog, click Continue in Safe ModeStart in Safe Mode.
3. Check whether your problem is still happening while in Safe Mode.

• If the problem still happens in Safe Mode, go on to step 4.
• If the problem does not happen in Safe Mode, see the Fejlsøg udvidelser, temaer og hardwareacceleration for at løse almindelige Firefox-problemer article and follow the instructions under The problem does not occur in Safe Mode to narrow down the cause.

4. Fejlsøg dine plugins

Sometimes plugins for Firefox (such as Adobe Reader, Flash, Java, QuickTime, RealPlayer, and Windows Media Player) can cause problems that may be fixed in the latest version. To check to see if you have the latest versions of all your plugins, go to our Plugin Check page If any of your plugins are out of date, click Update and follow the instructions for updating that plugin. After you've updated all of your plugins, restart Firefox: Skabelonen "closefirefox" findes ikke eller har ingen godkendt revision. then start Firefox again. If the problem still happens, you can disable all of your plugins to see if one of them is the cause:

If your problem goes away when all of your plugins are disabled, see the Fejlsøg problemer med plugins som Flash eller Java for at rette almindelige Firefox-problemer article to learn how to narrow down which one is causing it.

5. Geninstaller Firefox

Some Firefox issues can be caused by a problem with one of the Firefox program files. Follow these steps to completely remove and reinstall Firefox.

Now start Firefox and check to see if your problem has been fixed. If it has, you can reinstall the extensions and themes you verified (in part 3 above) were not causing problems. If your problem hasn't been fixed continue with the next troubleshooting method.

6. Nulstil Firefox

The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information.

1. Klik på knappen , klik på Hjælp, og klik så på Mere teknisk information.
2. Klik på knappen Nulstil Firefox…. Klik på Nulstil Firefox i bekræftelsesvinduet, der åbnes. Firefox lukker ned for at nulstille sig selv.
3. Når Firefox er færdig, vises et vindue med en liste over dine importerede informationer. Klik på knappen Afslut. Firefox åbnes.
4. Vælg om Firefox skal gendanne alle vinduer og faneblade eller blot nogle af dem. Klik så på knappen Lad os komme i gang!.

1. Genstart din computer

Sometimes problems can be fixed by simply restarting your computer and then starting Firefox again.

2. Slet dine cookies og cache

Many problems with loading web pages can be resolved by clearing Firefox's cookies and cache:

1. Klik på menuknappen Billedet "fx57menu" findes ikke. for at åbne menuen.
2. Klik på Historik, og klik så på Ryd seneste historik…
3. Klik på rullemenuen ud for Fjern, og vælg hele min historik.
4. Sæt flueben ud for både Cookies og Cache under Historik. Sørg for, at andre elementer, du vil beholde, ikke er valgt.
5. Klik på knappen OKRyd nu.

3. Genstart Firefox i fejlsikret tilstand

Fejlsikret tilstand is a troubleshooting mode that disables all extensions, uses the default theme, turns off hardware acceleration, and uses default toolbar settings and controls, among other things. To start Firefox in Safe Mode:

1. Klik på menuknappen . Klik på Hjælp, og klik så på Fejlsøgnings-tilstand…. Klik på knappen Genstart i vinduet Genstart Firefox i fejlsøgnings-tilstand?

   Bemærk: Du kan også starte Firefox i fejlsøgnings-tilstand ved at holde tasten Skift nede, mens Firefox startes. holde tasten Alternativ nede, mens Firefox startes. afslutte Firefox og i Terminal starte Firefox med kommandoen firefox -safe-mode
   Du kan være nødt til at angive stien til Firefox-installationen (fx /usr/lib/firefox)
2. In the Firefox Safe Mode dialog, click Continue in Safe Mode.
3. Check whether your problem is still happening while in Safe Mode.

• If the problem still happens in Safe Mode, go on to step 4.
• If the problem does not happen in Safe Mode, see the Fejlsøg udvidelser, temaer og hardwareacceleration for at løse almindelige Firefox-problemer article and follow the instructions under The problem does not occur in Safe Mode to narrow down the cause.

4. Fejlsøg dine plugins

Sometimes plugins for Firefox (such as Adobe Reader, Flash, Java, QuickTime, RealPlayer, and Windows Media Player) can cause problems that may be fixed in the latest version. To check to see if you have the latest versions of all your plugins, go to our Plugin Check page If any of your plugins are out of date, click Update and follow the instructions for updating that plugin. After you've updated all of your plugins, restart Firefox: Skabelonen "closefirefox" findes ikke eller har ingen godkendt revision. then start Firefox again. If the problem still happens, you can disable all of your plugins to see if one of them is the cause:

1. Klik på menuknappen , klik på Tilføjelser og temaer, og klik så på Plugins.
2. Click each plugin in the list and then click Disable.
3. Check whether your problem happens when you have all plugins disabled.

If your problem goes away when all of your plugins are disabled, see the Fejlsøg problemer med plugins som Flash eller Java for at rette almindelige Firefox-problemer article to learn how to narrow down which one is causing it.

5. Nulstil dine Firefox indstillinger

Some problems can be fixed by resetting your Firefox preference settings:

1. Klik på menuknappen . Klik på Hjælp, og klik så på Fejlsøgnings-tilstand…. Klik på knappen Genstart i vinduet Genstart Firefox i fejlsøgnings-tilstand?

   Bemærk: Du kan også starte Firefox i fejlsøgnings-tilstand ved at holde tasten Skift nede, mens Firefox startes. holde tasten Alternativ nede, mens Firefox startes. afslutte Firefox og i Terminal starte Firefox med kommandoen firefox -safe-mode
   Du kan være nødt til at angive stien til Firefox-installationen (fx /usr/lib/firefox)
2. In the Firefox Safe Mode dialog, click to put a check mark by Reset all user preferences to Firefox defaults.
3. To apply your changes, click Make Changes and Restart.

6. Geninstaller Firefox

Some Firefox issues can be caused by a problem with one of the Firefox program files. Follow these steps to completely remove and reinstall Firefox.

Now start Firefox and check to see if your problem has been fixed. If it has, you can reinstall the extensions and themes you verified (in part 3 above) were not causing problems. If your problem hasn't been fixed continue with the next troubleshooting method.

7. Lav en ny profil

A bad profile can cause all kinds of problems with Firefox. To see whether your problem is caused by a bad profile, make a new one. If that fixes the problem, you can copy your data (bookmarks, saved passwords, etc.) over to the new profile.

1. Use the instructions in the Brug Profilmanageren til at oprette og fjerne Firefox-profiler article to start the Profile Manager and create a new profile.
   When creating a new profile, do not delete your old profile. You will lose all of your bookmarks, history, passwords and settings.
2. Once you've created a new profile, select it in the Profile Manager and click Start Firefox.

Test to see if your problem occurs with the new profile. If it doesn't, you can copy your data to the new profile - see Genskab vigtige data fra en gammel profil for instructions.

Kontroller for konflikter med dit Internet sikkerheds software

Some Internet security software (including antivirus, antispyware, and firewall programs) can cause problems with Firefox including blocking it from opening websites, crashes, and more. Often you can open the program's settings, remove Firefox from its list of allowed or trusted programs and it will be re-detected and things should start working again. If your program is listed at the Konfigurer din firewall, så Firefox kan få adgang til Internettet article, you can get specific instructions for how to properly reconfigure it.

Skan dit system for virusser og spyware

Periodically, you should scan your system for viruses, spyware, or other malware. These free malware removal tools are often useful:

• Malwarebytes' Anti-Malware Free
• Microsoft Safety Scanner

If you need more help removing malware, see Fejlsøg Firefox-problemer som skyldes malware.

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