The Roku Express HD (model 3960) is currently on sale for $20 so a very good deal. Generally, usually recommend the Express 4k+ (3941) because a better device and comes with a better Voice Remote, but since you already had the Stick, you can pair your Voice Remote with the new Express. You do not need a 4k tv to use a 4k device (4k models just support that as the highest resolution).
Just make sure the Express HD is the new model 3960. This model is now dual band. Older models of the Roku Express HD just weren't the greatest as they were "starter models" for users. For $20, I would probably go with the 3960 HD. If it weren't on sale, I would buy the 4k+ 3941or wait for it to go on sale.
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As for your router, post your model number and ISP (internet service provider). As a general rule, even the most locked down routers will let you change the SSID name and password. If you mean you can't find anywhere in the Roku online dashboard to change your network settings, you are correct. All those changes must be made on the device.
As an additional test, if you have a mobile hotspot available to you (on your mobile phone), you can always try to connect the Stick to that if you want to rule out a network issue.
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When all else fails, usually recommend trying to do one final "Factory Reset" (press and hold reset for 30+ seconds). Then connect to mobile hotspot if available. If not, continue with available network. Select the 720p Display option when presented. (do not let the device perform an "auto-detect"). If you get the same result as you are experiencing currently, then can be pretty confident an internal hardware failure.
The startup bouncing letters are at a low resolution that should be viewable on just about any set. Once it boots up far enough to read its saved settings, it switches to the resolution the Roku has been set to. Your current Roku somehow may have gotten set to a higher resolution than your TV supports. When you then can't see what you're doing that makes it hard to change this setting.
If all else fails, you can try to adjust the Settings > Display type setting when you can't see the screen. After booting up the Roku and getting past the bouncing letters startup display:
A• Press the remote Home button at least 2 times (Makes sure you're on the home screen at correct position with no screen saver running)
B• Up (Go to Settings)
C• OK or Right (Go into Settings options)
D• Down 3 times (Highlight Display type. It passes through Theme on the way and this may take a few seconds before moving on) so wait 30 seconds or so before continuing.
D• OK (Chooses Display Type option)
F• Up (Moves off current Display Type setting to next one up)
G• OK (Selects this Display Type setting)
At this point, the Roku will try to use the selected Display Type setting. The TV may take a few seconds to adjust to this new setting.
If you see a picture, click the "Yes, looks good" button to lock in this setting.
If you don't see anything, wait about 15 seconds, then hit OK to click the unseen default "No, there's a problem" button to return you to the menu.
H• If you have not found a resolution setting that works, repeat steps F and G to try the next Display option. Repeat until you find one that works.
All of this stuff is pure nonsense. I've used just my modem. Not working. I've used my router, without VPN, not working. Used my router with VPN, not working. Spent $500.00 for a top end streaming router. With VPN, not working. Without VPN, not working. I've tried every possible way of unlocking the Roku channel and it still doesn't work after 6 months. I've spent a lot of money to try to resolve this. The new router does 100mb/second. It's your **bleep** app Roku! You aren't doing anything to fix it, so it tells me that you're participating in Geo-blocking. Tell me I'm wrong? I'll wait! No answer is an answer. This garbage has been going on for a full year. If I had known your product was doing this, I wouldn't have bought in to it. 4 different devices and all are doing the same.
@AvsGunnar Thanks for all the advice. I got a Roku Express for $20 on Amazon and set up last night. It was a breeze. I tried using the better remote from my Roku stick (the one with voice control) and it will power the TV off and on, and the volume button on the sides works, but nothing else works. However, the new "simple" remote works fine for what it does. So, between the two of them everything works, but I don't know how to get the remote with more features to work more than it does. Thanks again for your help. I tried it all, but it was clear that the device had a problem.
You will likely need to re-pair the Voice remote (the one from the Stick) to your new Express.
Make sure you remove power from your old Roku device. Then take the Voice Remote near the new Express and press the pairing button until it turns green. (likely under the battery cover). Then you should see it pair to the new Express. Sometimes you may need to restart the Roku device in order to get the pairing process to begin. (normally though pressing the button until it flasheds green should start the pairing process).
The Roku remotes can only control one Roku device at a time. (hence, the need to "pair" it to a device).
Here is Roku Support article on pairing remotes.
https://support.roku.com/article/360011621473
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Good to hear you are getting back up and running. 👍
I have responded in your other thread just now if you want to troubleshoot that particular issue so as not to get off topic in this thread. Feel free to reply in the other thread.