SUMMARY
Wireless components cannot connect to new router. This happens even if the wireless security is switched off, the encryptions is changed, or if the technology is forced to b, b+g  or even b+g+n protocols. The OS simply fails to connect to this router even if passwords are switched off. All other PCs and mobile phones connects to the router with no problems.


STEPS TO REPRODUCE
1. Setup a TP-Link TL-MR6400 router
2. Attempt to connect to the WiFi Lan

OBSERVED RESULT
Oct  9 06:21:57 localhost NetworkManager[978]: <info>  [1539058917.0694] device (wlp4s0): Activation: starting connection 'TP-Link_9798' (e11731e1-256e-43b4-bee4-88f9c879a160)
Oct  9 06:21:57 localhost NetworkManager[978]: <info>  [1539058917.0697] audit: op="connection-activate" uuid="e11731e1-256e-43b4-bee4-88f9c879a160" name="TP-Link_9798" pid=2102 uid=1000 result="success"
Oct  9 06:21:57 localhost NetworkManager[978]: <info>  [1539058917.0701] device (wlp4s0): state change: disconnected -> prepare (reason 'none', internal state 'managed')
Oct  9 06:21:57 localhost NetworkManager[978]: <info>  [1539058917.0774] device (wlp4s0): set-hw-addr: reset MAC address to 1C:65:9D:E5:F0:8B (preserve)
Oct  9 06:21:57 localhost kernel: ieee80211 phy0: RTL8225-SE version not-D
Oct  9 06:21:57 localhost kernel: ieee80211 phy0: NO Xtal cal
Oct  9 06:21:57 localhost kernel: IPv6: ADDRCONF(NETDEV_UP): wlp4s0: link is not ready
Oct  9 06:21:57 localhost NetworkManager[978]: <info>  [1539058917.9853] device (wlp4s0): supplicant interface state: inactive -> disabled
Oct  9 06:21:57 localhost NetworkManager[978]: <info>  [1539058917.9879] device (wlp4s0): state change: prepare -> config (reason 'none', internal state 'managed')
Oct  9 06:21:57 localhost NetworkManager[978]: <info>  [1539058917.9930] device (wlp4s0): Activation: (wifi) access point 'TP-Link_9798' has security, but secrets are required.
Oct  9 06:21:57 localhost NetworkManager[978]: <info>  [1539058917.9942] device (wlp4s0): state change: config -> need-auth (reason 'none', internal state 'managed')
Oct  9 06:21:57 localhost NetworkManager[978]: <info>  [1539058917.9977] device (wlp4s0): supplicant interface state: disabled -> inactive
Oct  9 06:21:58 localhost kdeinit5[2070]: plasma-nm: Unhandled active connection state change:  1
Oct  9 06:21:58 localhost NetworkManager[978]: <info>  [1539058918.0810] device (wlp4s0): state change: need-auth -> prepare (reason 'none', internal state 'managed')
Oct  9 06:21:58 localhost NetworkManager[978]: <info>  [1539058918.0838] device (wlp4s0): state change: prepare -> config (reason 'none', internal state 'managed')
Oct  9 06:21:58 localhost NetworkManager[978]: <info>  [1539058918.0861] device (wlp4s0): Activation: (wifi) connection 'TP-Link_9798' has security, and secrets exist.  No new secrets needed.
Oct  9 06:21:58 localhost NetworkManager[978]: <info>  [1539058918.0869] Config: added 'ssid' value 'TP-Link_9798'
Oct  9 06:21:58 localhost NetworkManager[978]: <info>  [1539058918.0878] Config: added 'scan_ssid' value '1'
Oct  9 06:21:58 localhost NetworkManager[978]: <info>  [1539058918.0885] Config: added 'key_mgmt' value 'WPA-PSK'
Oct  9 06:21:58 localhost NetworkManager[978]: <info>  [1539058918.0892] Config: added 'psk' value '<hidden>'
Oct  9 06:21:58 localhost NetworkManager[978]: <info>  [1539058918.1746] device (wlp4s0): supplicant interface state: inactive -> scanning
Oct  9 06:21:59 localhost wpa_supplicant[1337]: wlp4s0: SME: Trying to authenticate with 7c:8b:ca:f3:97:98 (SSID='TP-Link_9798' freq=2462 MHz)
Oct  9 06:21:59 localhost kernel: wlp4s0: authenticate with 7c:8b:ca:f3:97:98
Oct  9 06:21:59 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 1/3)
Oct  9 06:21:59 localhost NetworkManager[978]: <info>  [1539058919.4222] device (wlp4s0): supplicant interface state: scanning -> authenticating
Oct  9 06:21:59 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 2/3)
Oct  9 06:21:59 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 3/3)
Oct  9 06:22:00 localhost kernel: wlp4s0: authentication with 7c:8b:ca:f3:97:98 timed out
Oct  9 06:22:00 localhost NetworkManager[978]: <info>  [1539058920.1122] device (wlp4s0): supplicant interface state: authenticating -> disconnected
Oct  9 06:22:00 localhost NetworkManager[978]: <info>  [1539058920.2308] device (wlp4s0): supplicant interface state: disconnected -> scanning
Oct  9 06:22:01 localhost wpa_supplicant[1337]: wlp4s0: SME: Trying to authenticate with 7c:8b:ca:f3:97:98 (SSID='TP-Link_9798' freq=2462 MHz)
Oct  9 06:22:01 localhost kernel: wlp4s0: authenticate with 7c:8b:ca:f3:97:98
Oct  9 06:22:01 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 1/3)
Oct  9 06:22:01 localhost NetworkManager[978]: <info>  [1539058921.4825] device (wlp4s0): supplicant interface state: scanning -> authenticating
Oct  9 06:22:01 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 2/3)
Oct  9 06:22:01 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 3/3)
Oct  9 06:22:02 localhost kernel: wlp4s0: authentication with 7c:8b:ca:f3:97:98 timed out
Oct  9 06:22:02 localhost NetworkManager[978]: <info>  [1539058922.1660] device (wlp4s0): supplicant interface state: authenticating -> disconnected
Oct  9 06:22:02 localhost NetworkManager[978]: <info>  [1539058922.6918] device (wlp4s0): supplicant interface state: disconnected -> scanning
Oct  9 06:22:03 localhost kernel: wlp4s0: authenticate with 7c:8b:ca:f3:97:98
Oct  9 06:22:03 localhost wpa_supplicant[1337]: wlp4s0: SME: Trying to authenticate with 7c:8b:ca:f3:97:98 (SSID='TP-Link_9798' freq=2462 MHz)
Oct  9 06:22:03 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 1/3)
Oct  9 06:22:03 localhost NetworkManager[978]: <info>  [1539058923.9365] device (wlp4s0): supplicant interface state: scanning -> authenticating
Oct  9 06:22:04 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 2/3)
Oct  9 06:22:04 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 3/3)
Oct  9 06:22:04 localhost kernel: wlp4s0: authentication with 7c:8b:ca:f3:97:98 timed out
Oct  9 06:22:04 localhost NetworkManager[978]: <info>  [1539058924.6248] device (wlp4s0): supplicant interface state: authenticating -> disconnected
Oct  9 06:22:05 localhost NetworkManager[978]: <info>  [1539058925.6422] device (wlp4s0): supplicant interface state: disconnected -> scanning
Oct  9 06:22:06 localhost kernel: wlp4s0: authenticate with 7c:8b:ca:f3:97:98
Oct  9 06:22:06 localhost wpa_supplicant[1337]: wlp4s0: SME: Trying to authenticate with 7c:8b:ca:f3:97:98 (SSID='TP-Link_9798' freq=2462 MHz)
Oct  9 06:22:06 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 1/3)
Oct  9 06:22:06 localhost NetworkManager[978]: <info>  [1539058926.9041] device (wlp4s0): supplicant interface state: scanning -> authenticating
Oct  9 06:22:07 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 2/3)
Oct  9 06:22:07 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 3/3)
Oct  9 06:22:07 localhost kernel: wlp4s0: authentication with 7c:8b:ca:f3:97:98 timed out
Oct  9 06:22:07 localhost wpa_supplicant[1337]: wlp4s0: CTRL-EVENT-SSID-TEMP-DISABLED id=0 ssid="TP-Link_9798" auth_failures=1 duration=10 reason=CONN_FAILED
Oct  9 06:22:07 localhost NetworkManager[978]: <info>  [1539058927.5820] device (wlp4s0): supplicant interface state: authenticating -> disconnected
Oct  9 06:22:12 localhost NetworkManager[978]: <info>  [1539058932.6046] device (wlp4s0): supplicant interface state: disconnected -> scanning
Oct  9 06:22:17 localhost wpa_supplicant[1337]: wlp4s0: CTRL-EVENT-SSID-REENABLED id=0 ssid="TP-Link_9798"
Oct  9 06:22:17 localhost wpa_supplicant[1337]: wlp4s0: SME: Trying to authenticate with 7c:8b:ca:f3:97:98 (SSID='TP-Link_9798' freq=2462 MHz)
Oct  9 06:22:17 localhost kernel: wlp4s0: authenticate with 7c:8b:ca:f3:97:98
Oct  9 06:22:17 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 1/3)
Oct  9 06:22:17 localhost NetworkManager[978]: <info>  [1539058937.7937] device (wlp4s0): supplicant interface state: scanning -> authenticating
Oct  9 06:22:17 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 2/3)
Oct  9 06:22:18 localhost kernel: wlp4s0: send auth to 7c:8b:ca:f3:97:98 (try 3/3)
Oct  9 06:22:18 localhost kernel: wlp4s0: authentication with 7c:8b:ca:f3:97:98 timed out
Oct  9 06:22:18 localhost wpa_supplicant[1337]: wlp4s0: CTRL-EVENT-SSID-TEMP-DISABLED id=0 ssid="TP-Link_9798" auth_failures=2 duration=20 reason=CONN_FAILED
Oct  9 06:22:18 localhost NetworkManager[978]: <info>  [1539058938.4722] device (wlp4s0): supplicant interface state: authenticating -> disconnected
Oct  9 06:22:23 localhost NetworkManager[978]: <warn>  [1539058943.4045] device (wlp4s0): Activation: (wifi) association took too long, failing activation
Oct  9 06:22:23 localhost NetworkManager[978]: <info>  [1539058943.4046] device (wlp4s0): state change: config -> failed (reason 'ssid-not-found', internal state 'managed')
Oct  9 06:22:23 localhost NetworkManager[978]: <warn>  [1539058943.4062] device (wlp4s0): Activation: failed for connection 'TP-Link_9798'
Oct  9 06:22:23 localhost kernel: IPv6: ADDRCONF(NETDEV_UP): wlp4s0: link is not ready
Oct  9 06:22:23 localhost NetworkManager[978]: <info>  [1539058943.4129] device (wlp4s0): state change: failed -> disconnected (reason 'none', internal state 'managed')
Oct  9 06:22:24 localhost kernel: ieee80211 phy0: RTL8225-SE version not-D
Oct  9 06:22:24 localhost akonadi_ical_resource[2521]: "No such interface 'org.freedesktop.DBus.Properties' on object at path /org/freedesktop/NetworkManager/ActiveConnection/2"
Oct  9 06:22:24 localhost akonadi_notes_agent[2566]: "No such interface 'org.freedesktop.DBus.Properties' on object at path /org/freedesktop/NetworkManager/ActiveConnection/2"
Oct  9 06:22:24 localhost kernel: ieee80211 phy0: NO Xtal cal
Oct  9 06:22:24 localhost NetworkManager[978]: <info>  [1539058943.4204] device (wlp4s0): set-hw-addr: set MAC address to 8A:BF:A2:1D:12:F7 (scanning)
Oct  9 06:22:24 localhost akonadi_followupreminder_agent[2520]: "No such interface 'org.freedesktop.DBus.Properties' on object at path /org/freedesktop/NetworkManager/ActiveConnection/2"
Oct  9 06:22:24 localhost kernel: IPv6: ADDRCONF(NETDEV_UP): wlp4s0: link is not ready
Oct  9 06:22:24 localhost akonadi_maildispatcher_agent[2541]: "No such interface 'org.freedesktop.DBus.Properties' on object at path /org/freedesktop/NetworkManager/ActiveConnection/2"
Oct  9 06:22:24 localhost akonadi_sendlater_agent[2571]: "No such interface 'org.freedesktop.DBus.Properties' on object at path /org/freedesktop/NetworkManager/ActiveConnection/2"
Oct  9 06:22:24 localhost kdeinit5[2070]: "No such interface 'org.freedesktop.DBus.Properties' on object at path /org/freedesktop/NetworkManager/ActiveConnection/2"
Oct  9 06:22:24 localhost kdeconnectd[2105]: "No such interface 'org.freedesktop.DBus.Properties' on object at path /org/freedesktop/NetworkManager/ActiveConnection/2"
Oct  9 06:22:24 localhost NetworkManager[978]: <info>  [1539058944.3745] device (wlp4s0): supplicant interface state: disconnected -> inactive
Oct  9 06:22:24 localhost wpa_supplicant[1337]: wlp4s0: Reject scan trigger since one is already pending

EXPECTED RESULT
Wireless Lan should connect to modern routers

SOFTWARE VERSIONS
(available in About System)
KDE Plasma Version: 5.10.5
KDE Frameworks Version: 5.44.0
Qt Version: 5.9.4

ADDITIONAL INFORMATION
- none -