Hi sidv13, when there are no errors displayed, it is more difficult to figure out why Firefox is failing to launch normally, or whether Windows or a security program is "killing" Firefox early in its launch. If you try again right away, does Firefox say it is running and needs to be closed first, or does it behave like it's not running on the next try? ---- Perhaps you're encountering this issue for several months ago: '''''A Recent Issue for 64-bit Windows Users with 64-bit Firefox''''' Before Firefox 56.0.1, users of 64-bit Windows generally were using the traditional 32-bit version of Firefox. However, newer versions may switch you to the 64-bit version. We received a number of puzzling reports of Firefox either not starting or not loading any pages after this migration. One user discovered that Windows was silently killing Firefox at startup and recording it in the Windows event logs (you can view event logs using the Event Viewer). Based on one of the reports in the log, we were able to trace that to an out-of-date Logitech camera driver, of all things. By now at least six other users reported that uninstalling or updating the Logitech camera software resolved their problem as well. * https://support.mozilla.org/questions/1179822#answer-1019375 * https://support.mozilla.org/questions/1181740#answer-1021470 * https://support.mozilla.org/questions/1181405#answer-1022798 * https://support.mozilla.org/questions/1182572#answer-1023413 * https://support.mozilla.org/questions/1182847#answer-1024290 * ''With 57:'' https://support.mozilla.org/questions/1188971 * https://support.mozilla.org/questions/1191368#answer-1041814 Do you want some assistance in looking at event logs, or do you have such a webcam?