I'm having the same problem. Won't connect even though my password is correct. All other devices in the house connect fine using the same password. I tried rebooting the router and the fire stick. It's definitely some problem with the fire stick itself.
Unplugged my router and then plugged it back in and it fixed the problem once I signed back in to my WiFi on the fire stick. Not sure why it worked since I still had WiFi connectivity for phones, cams etc before rebooting the router.
This issue just started happening to me. About two weeks ago my firestick kicked me off my network randomly. I tried to reconnect using the CORRECT PASSWORD (tested this on other devices) and it won't connect to my network. It keeps stating that my password is incorrect even though i had verified that it IS CORRECT.
Four days later I try the same password I have been trying and it connects. I am able to use the fire TV for a few days and then it kicks me off again. Same problem. CORRECT PASSWORD but will not connect.
This is a real issue that is happening with the devices and i hope there is a solution soon.
Not only have I restarted the device multiple times (unplugging as well) I have also moved to a different city. Set up my new network and the fire tv still will not connect to the new network with the CORRECT PASSWORD. (emphasis since no one seems to understand this issue)
I honestly think I am done with the Fire products. I have had this issue for weeks with no solution.
A couple of other suggestions. Using the Fire TV involves TWO passwords. One for your Amazon account and one for your router's wifi access. Are you sure you are entering the correct password - making sure to use capital letters where required?
And it always makes sense to unplug the router and device from power briefly. Unforseen programming errors routinely exist in complex products like these.
I've found this post by asking Google about firestick wifi password problems and I can confirm the people above are correct, Amazon has an issue with the current firestick network adaptor driver/android config.
The stick worked fine for months then back in January it randomly started saying it was connected to Wi-Fi but couldn't get internet from my router, however plenty of other devices connected to same Wi-Fi without issue including 2 Fire tablets.
After changing my router to another top of the range non-ISP programmed router I still have the same issue. I admit the only thing I've not tried is a factory reset of the Firestick as it's setup with lots of 3rd party android apps but the point is Amazon broke something in an update and from reading above it seems the only fix is a factory reset.
The only temporary fix is to do forget Wi-Fi (if connected) and reboot the stick or if you can't connect at all I found entering the password correctly and being rejected then rebooting the stick after the reboot it would accept the password.
Anyone who hasn't experienced this problem and goes on about not knowing passwords can't weight in here because your assuming the above posters have ISP provided routers for a start. I hope you don't get the problem because it is very annoying.
I hope you figured this out since it was a while ago. I just set up a new router, everything was working. Walked away from the tv, come back and suddenly, not connected. Keeps saying my password was incorrect, etc. Everything else was connected. No issues. I went to settings, device, restart. Came back on, went to network, put my password in, connected with no issues. Sometimes the fire sticks cache gets stuck. No matter how many times I scanned the network, it was trying to log into the old router with the same name. Hope this helps someone.
I am now experiencing this same issue. I disconnected my Ethernet for WiFi but I keep getting the “WiFi password invalid” or from time to time a “WiFi Error, And unexpected error has occurred. Please try again.” message. All three of our other FireTV and our Alexa devices are fine. Really frustrating to have to reset to factory settings and lose all of my customization. This is a silly problem that didn’t exist prior because I’ve done this before without issue.
HASH TAG ME TOO! Got 2 firestick 4ks on separate TVs, one WIFI connected to the primary router and the other wifi connected to a repeater router. Both have been working fine for months and then yesterday the one connected to the primary router lost connection and during the settings reconfig, started throwing the invalid wifi password error. Tried disconnecting for a couple of minutes with no luck. Then I swapped both firesticks so they were working with the other TV and router and hey presto they both work. How long this lasts I don't know.
For me this is becoming a weekly task of forget, reboot and enter password. I will likely factory reset but I wonder if that will truly solve the issue or if it will come back. Amazon need to comment on this if they're working to resolve or can replicate the problem?
I have 5 Firesticks with 4 Wifi networks (one network and stick at our vacation location). I have never had an issue with the sticks not recognizing the wifi password for the network. I have never requested that amazon store my network password and 3 of my wifi networks are behind my Hyper V virtual firewall device. In testing my networks to decide the optimal router locations with respect to the firesticks and recast box, I have had to re-enter network passwords many times without any issues. My only complaint is that the fire stick devices remember the network password and upon the re-selection of a new/previous network; however, I have to re-enter the passwords after the initial setup when changing the Recast among my three networks. I have a two year old stick, two 4K sticks and two regular sticks purchased last November. I have had one stick failure that continually rebooted and Amazon replaced the stick promptly. I agree with Roginator that this might be an operator issue and not a FireStick issue. The cache issue identified by bcisaidso is an interesting point that may be applicable. My tests show that even though Amazon is not storing my network password, it does retain the passwords associated with each network (in my case three), there may be an issue if the replacement router is given the same name and new password. I also have not experienced the case where the stick is requesting a password that has already been entered (other than the Recast box) so there could be an issue there.