X64 Uninstaller is Fake
Your TP2 x64 build is not able to be uninstalled from C:\Program Files. An item appears in the Windows program list to uninstall but doing so only removes it from the list and leaves both the files and the registry keys. This is both annoying and quite troubling. You need to fix this immediately. A tech preview shouldn't mean that the uninstaller also isn't guaranteed to work.
maybe try running it as administrator(?) - via the uninstaller in the folder.
or wise uninstaller, revo uninstaller, advanced uninstaller pro.
i know advanced uninstaller pro has a 64 bit program. it likes to try and sneak in some bundled stuff though. but it also has a registry snap shot feature (before install and after) that rocks when this happens.
or if you have ccleaner, it has an unistaller in it, so you can run ccleaner as administrator and then uninstall through it. then you can do a registry scan with it.
i hate when uninstallers don't work. sometimes its best to just use sandboxie to test the program first.
Two years later and the problem is still there for both 32bit and 64bit (under Win 7 64bit). Uninstalling either of them leaves behind a perfectly functional Vivaldi.
If you found a bug, please report the issue to the developers to fix it.
How to do a bugreport for Vivaldi
Report each bug seperately at https://vivaldi.com/bugreport/
Describe the issue as precise as you can.
Add some information about extensions you use.
Add information about the operating system and version you use.
if you have problems with video or audio give us information about your installed codecs and graphics card/GPU.
Add a link to a testpage where the issue comes up and can be tested.
After reporting the issue, you will receive a confirmation mail from the bugtracker.
In a reply to this mail you can add more information and files (like screenshots or testcases) as attachments and it will be added automatically to bug report.
If you have questions about the bug please ask in forum first and do not forget to post the VB-XXXXX bug number (you can find it in confirmation mail).
Thanks in advance for helping us to make Vivaldi better!