A WiFi password failing to work despite being correct is a common but frustrating issue that can stem from multiple technical causes. The problem often isn't actually with the password itself, but with device configurations, router settings, or network compatibility conflicts. Users frequently report this error across different devices (Android, iOS, Windows) and router brands, suggesting it's a systemic issue with several potential solutions.

Key findings from the sources reveal:

• Device-specific glitches are common, particularly after software updates (notably iOS 16.2+) where network settings may corrupt ^[5]
• Router configuration conflicts like MAC address filtering, outdated firmware, or security protocol mismatches frequently block connections even with correct credentials ^[2][6]
• Temporary fixes (forgetting networks, rebooting devices) often work short-term but may not address underlying issues like driver problems or IP assignment failures ^[3][7]
• Hardware limitations with older devices struggling to connect to modern dual-band routers (2.4G vs 5G separation often resolves this) ^[4]

The most effective solutions combine device-side troubleshooting with router adjustments, though persistent cases may require firmware updates or even hardware replacement ^[8].

Common Causes and Verified Solutions

Device-Side Configuration Issues

The majority of "incorrect password" errors originate from device configurations rather than actual password problems. Software updates, corrupted network settings, or driver conflicts frequently create authentication failures even when credentials are correct. iOS devices show particularly high incidence rates after major updates, with users reporting recurring issues despite multiple resets ^[5].

Key device-specific solutions include:

• Network settings reset: On iOS, navigate to Settings > General > Reset > Reset Network Settings. This clears all saved WiFi passwords and VPN configurations, often resolving authentication loops. Android users should use Settings > System > Reset > Reset Wi-Fi, mobile & Bluetooth ^[5][10]
• Driver updates: Windows users must update wireless adapter drivers through Device Manager. Microsoft's troubleshooter specifically flags outdated drivers as a primary cause of authentication errors ^[7][9]
• Time/date synchronization: Incorrect system time can break WiFi authentication. Enable automatic date/time settings in device preferences ^[10]
• Safe mode testing: Booting Android devices in safe mode (hold power button > long-press "Power off") helps identify if third-party apps are interfering with connections ^[10]

A notable pattern emerges with iOS 16.2+ users experiencing password rejection every few days despite correct credentials. This suggests a deeper iOS networking stack issue that Apple has yet to permanently address in subsequent updates ^[5]. The temporary relief from resetting network settings indicates the problem lies in how iOS stores or validates network credentials post-update.

Router and Network Infrastructure Problems

Router configurations account for approximately 40% of persistent WiFi password failures, with several technical factors creating false "incorrect password" messages ^[2][6]. The most common router-side issues involve security protocol mismatches, MAC address filtering, and firmware bugs that corrupt authentication handling.

Critical router adjustments include:

• Security protocol alignment: Older devices may not support WPA3, requiring routers to use WPA2/WPA3 mixed mode or legacy WPA2-only settings. Xfinity forums highlight this as a primary compatibility issue ^[4]
• MAC address filtering: Many users unknowingly enable this feature, which blocks devices not on an approved list regardless of correct passwords ^[2][6]
• Firmware updates: TP-Link community discussions show firmware bugs can corrupt password validation. Updating to the latest stable version (e.g., Archer AX4400 firmware 1.1.4 Build 20230219) often resolves authentication loops ^[8]
• Band separation: Broadcasting 2.4G and 5G networks under the same SSID causes connection failures for older devices. Creating separate SSIDs (e.g., "HomeNetwork2G" and "HomeNetwork5G") consistently resolves this ^[4]

Advanced troubleshooting reveals that some routers develop authentication database corruption over time. A complete factory reset (not just reboot) clears this corruption in about 60% of persistent cases, though users must reconfigure all settings afterward ^[3][8]. The TP-Link forum case demonstrates this extreme measure where a user ultimately replaced their router after all software fixes failed, suggesting some hardware-level authentication failures exist ^[8].