Windows 10 bereikte EO (einde ondersteuning) op 14 oktober 2025. Als je Windows 10 gebruikt, lees dan dit artikel.

Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

Zoeken in Support

Vermijd ondersteuningsscams. We zullen u nooit vragen een telefoonnummer te bellen, er een sms naar te sturen of persoonlijke gegevens te delen. Meld verdachte activiteit met de optie ‘Misbruik melden’.

Meer info
Deze conversatie is gesloten en gearchiveerd. Stel een nieuwe vraag als u hulp nodig hebt.
Solved Locked Gearchiveerd

Trying to open Firefox today I get the message: A copy of Firefox is already open. Only one copy of Firefox can be open at a time. 'm stuck!

FredMcD beantwoord
SuMo Bot

I can't access Firefox. Get message: A copy of Firefox is already open. Only one copy of Firefox can be open at a time.

Firefox is not open and I need it!

I can't access Firefox. Get message: A copy of Firefox is already open. Only one copy of Firefox can be open at a time. Firefox is not open and I need it!
Dit antwoord in context lezen

Gekozen oplossing

Macs: Make sure you install Firefox properly and that you do not run Firefox from within the DMG (Disk Images) file. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Alle antwoorden (5)

iMac OS 11.3.1 Can't identify FF version as can't open it! Can't find FF in library or app support so can't find profile Really stuck.

Gekozen oplossing

Macs: Make sure you install Firefox properly and that you do not run Firefox from within the DMG (Disk Images) file. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Thank you so much! I didn't quite understand everything but by some magic it worked!! And Firefox is back with me and all seems to be in order.

Glad to help. Safe Surfing.

This question has been locked because the original author has deleted their account. While you can no longer post new replies, the existing content remains available for reference.