If you are looking for the decompiler itself, visit https://github.com/jindrapetrik/jpexs-decompiler
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List of issues#2177 Leftover processes after "Invalid SWF, wrong signature" error
Author: 
nosamu
nosamuDate created:
Type: bug
Visibility: Everybody
Assigned to:
Labels: Startup
State: upgraded 
> What steps will reproduce the problem?
1. Right-click any file with a .swf file extension that is not a valid SWF file.
2. Click "Open with FFDec".
3. When the "Invalid SWF, wrong signature" error appears, click OK.
4. Check Task Manager. A "JPEXS Free Flash Decompiler Launcher" process and "Java Platform
SE binary" process will be visible.
> What is the expected output? What do you see instead?
The FFDec and Java processes should stop after I click the OK button.
> What version of the product are you using? Is it "nightly build"? Which operating system
do you have?
FFDec version: 20.1.0 (stable)
Operating system: Windows 10 64-bit
> Please provide any additional information below. If the problem is related to a SWF
file, attach it here, otherwise we can't help you.
The problem also happens for the "SWF header is too short" error. So a blank .txt file
renamed to .swf can also trigger the problem.
In nightly 2760, main window in shown in such cases,
which you can close to terminate process.
State: new→upgraded
Great, thank you!