The short answer
- Photograph or copy the complete 0x11C7 message and file name before changing anything.
- Restart Windows, install pending Windows Security and game updates, then use Steam's Verify integrity of game files.
- Remove mods, replacement executables or unofficial launchers from the test; if verification cannot restore a clean copy, reinstall once from Steam.
- Do not download a 'fixed EXE' and do not disable Smart App Control as the first workaround—Microsoft says there is no per-app allow switch.
See it in the game
Videos open on YouTube. Unless a timestamp is cited in the Sources section, use them for visual context—not as a guaranteed drop table or fix.
First confirm this is the same error
Use this route when Windows says an application-control policy blocked a How to Fish file and the message includes 0x11C7. A plain crash, black screen, Steam Relay warning or missing lobby is a different branch and should not be treated as a Smart App Control problem.
Record the exact path and file name. If the blocked file sits in a mod folder, download folder or another unofficial location, do not run it. The target state is a clean copy installed and maintained by Steam.
Safe fix order
- 1
Close the game and Steam, then restart Windows.
- 2
Open Windows Update and Windows Security and install pending security intelligence, platform and operating-system updates.
- 3
Open Steam, update How to Fish, then choose Properties, Installed Files and Verify integrity of game files.
- 4
Temporarily remove third-party mods, DLL replacements, unofficial launchers or replacement executables from the test path.
- 5
Launch the verified game directly from Steam once.
- 6
If the same official file is still blocked, uninstall and reinstall the game from Steam once, then preserve the new message if it repeats.
Why disabling Smart App Control is not the first fix
Microsoft's Smart App Control FAQ says there is no way to bypass protection for a single app. Turning the feature off therefore changes protection for the whole system, not just How to Fish. Microsoft also documents that the feature may require a Windows reset to turn on again on some systems, although newer Windows versions can expose an option to reevaluate it.
That tradeoff is too large for an initial game fix. Verification, removal of unofficial files and a clean Steam reinstall are reversible and keep the security boundary intact. If Windows continues blocking an official file, send the evidence to the developer and Microsoft rather than downloading an unsigned substitute.
What to include in a useful report
- 1
The complete error text, including 0x11C7 and the blocked file name.
- 2
Your Windows version and whether Smart App Control shows On, Evaluation or Off in Windows Security.
- 3
Whether Steam verification replaced any files and whether the error survived a clean reinstall.
- 4
Whether the install ever contained mods, a replacement executable or security exclusions.
- 5
The current How to Fish build and the time the block occurred.
Do not use these shortcuts
Do not download a replacement EXE, copy a stranger's game DLL, add a broad antivirus exclusion or follow a command that disables application control globally. Those actions can hide the symptom while replacing a trusted distribution path with an unverified one.
Sources used on this page
Community observations are useful leads, but they are not official drop probabilities.