@Tokio Can you confirm how many characters of the password? Is it more than 15 characters? What if you change the password to something less than 15, will you be able to login?

@xokia Onemesh only works between Onemesh Router and Onemesh extenders, but not between two Onemesh routers. You can read about it there (Q10): https://www.tp-link.com/support/faq/2690/

@Yam1208 First, check that you have set the "Channel Width" in the router's 2.4 GHz wireless settings to "40MHz". Second, verify that your client device actually supports dual-stream (2×2) and 40 MHz...

@Pappuasa Which password are you referring to? The login password or the password for connecting to the wireless? Generally, the default username and password for login to the router is printed on...

@matisan100 As confirmed with the developers, there will be a final version in the near future, while we cannot give you an ETA right now, you can keep an eye on the official website by yourself.

@blackduck This is the beta firmware: https://static.tp-link.com/2020/202009/20200928/ArcherC5400v2_EU-up-ver1-2-4-P2[20180525-rel55808]_beta.zip