Check these in order
1. It is already running
w0a allows one instance. If a previous one is still running — including minimised to the notification area — a second double-click does nothing visible. Look for the icon next to the clock, and check Task Manager's Details tab for w0a.exe.
2. Your security tool took the file
Common enough to have its own page: My antivirus removed the file. If the file is gone from disk, this is why.
3. The download is incomplete
An interrupted download produces a file that looks fine and will not run. Compare the SHA-256 with the published one; if it does not match, download it again.
Get-FileHash .\w0a.exe -Algorithm SHA2564. It started and then failed
If the window appears and disappears, w0a wrote down why. Open this file:
%AppData%\w0a\errors.logPaste that path into the Explorer address bar. The last entries are the most recent. Nothing in that file is sent anywhere by itself — it is written locally so that you have something to send if you choose to.
Still nothing
Write to us with the last twenty lines of that log and your Windows version (press Win+R, type winver). Those two together identify almost every startup failure without another round of questions.
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