[Verizon HTC One (M8)] Casetheace:
I would believe that it would work using those links and the guide in it. Concern would be is the author of it clearly States enabling extra bands may break phone to point of RUU won't fix it. I can tell you on my Verizon m8 when I first used the DFS tool I had 4 Lt bands enabled, believe is was 2,4, 12 and maybe one more. So 3 or 4. I have it on T-Mobile sim, so. Was enabling 6 bands, at least 2 more then before. My first try I accidentally hit band 40 also so I was turning all T-Mobile bands on and a extra one. Now that didnt fry my radios. Noticed it on the first text to check if it worked. I'll write why I did, I think enabling just that one band won't kill it. Also if a band is active and you don't use it, maybe turn that off and 40 on. Okay heres my step by step guide it did.:

1. Downloaded DFS TOOl , free version is fine just takes extra time that's all.

2. Using command prompt., did the adb shell, then su, phone will ask for approval for supersu access. Then enter the code to turn hdiag on. You want to use the one for m8, first codes are for m9 , the m8 is clearly said in bold. Once entered to turn in on. Plug in your phone. Now run DFS with administrative rights, can't remember what the exact steps for the next things but just follow the guide. In DFS tool you should see your phone connect , not in usb mode, but cm 8 port, cm 7port. Now for the computer to read the phone in DIAG you need the driver, its in the m8 HTC sync manager thing. So if that's installed you have it already. Now if it's installed and you don't see it recognised in diag mode using device manager option your PC (by the way I'm running WIN 10 on my PC) I had read that I'm windows 8 it would not accept drivers without signatures. There is a guide in there explaining how to install under that. My phone was not picked up in DIAG mode, had sync manager , driver installed from DFS tool, then used a zip I'm authors guide. Unzipped folder and it was broken into folders. Have to find folder with exe to run it. After all this still no dice. Then went to device manager , went to phone where it stated driver missing. Douple clicked on it. Chose option to update driver, selected in there a option that will show you all the drivers installed on the device. Chose the HTCDIAGDRIVER. It installed it and had to reboot comp.

3. Now go back to DFS TOOL., follow the authors guide to the T in this process. You pick the last tab , LTE , I believe. Following guide, I let it read all my lte bands, wrote down all the current ones in case I needed to change it in time. Then chose to read again and write down LTE bands using authors guide, of the selection in bottom right of screen u need to chose. In guide it States the name of it, and to choose that and read. In that option In bottom right, there is another selection next to it, 3 of 4 same words can't remember the word but its in Authors guide. Now your gonna want to have what bands are currently enabled, in authors guide is what LTE bands should be choose by manufacturers default. I then choose the bands it had listed that should be, and deselected any bands that where not being used on current provider. Now you want to hit write after choosing your bands. Now after that you want to write the bands in next mode that author says to change just in case. OK, now you can't do both writes at same time. If you do, first write won't stick and only second. I tried and can tell you that. So write , reboot, write, reboot. Now after that, reconnect phone to PC and read both things you just changed to make sure they stuck.

4. Using command prompt on PC, adb shell, su , then code to turn the hdiag mode off. If you don't PC won't recognize the phone as prober driver and a DIAG mode. Make sure to do this.

That's what I did. I would advise to read all ten pages of former questions, lost of newer information that will only help you understand it more.

I'm far from a expert, I just know the adb commamd process, how to flash ROMs, mostly basic things. 4 Years ago I knew nothing. So I'm sure u can do it. Author will answer questions, mostly every question you can think of has been asked in those ten oahes and you will learn it from there. So i would read all posts so you have a good feel of it. Anything I can help you with write back. Havent been on in two weeks. Stock market has my attention 18hrs a day