Use Flash Player after 12 Jan 2021

Solution 1:

I managed to make the "time bomb defuser" work, as indicated here:

Disable EOL uninstall warnings:
    Disable auto updates when installing
    Add "EOLUninstallDisable=1" to mmc.cfg in C:\WINDOWS\system32\Macromed\Flash
    (C:\Windows\SysWOW64\Macromed\Flash on 64-bit)

---

Defuse flash player time bomb:

Time bomb trigger is the timestamp 1610409600000.0
encoded in double precision floating point (0x42776f3e46400000):
    00 00 40 46 3E 6F 77 42
replace with infinity:
    00 00 00 00 00 00 F8 7F

C:\WINDOWS\system32\Macromed\Flash
(C:\Windows\SysWOW64\Macromed\Flash on 64-bit)
    Flash32_32_0_0_453.ocx (offset: 453: E1D968, 465: E1DBD0)
    NPSWF32_32_0_0_453.dll (offset: 453: E3A2E0, 465: E3A32A)
    pepflashplayer32_32_0_0_453.dll (offset: 453: CBFCE0, 465: CBFCB8)

C:\WINDOWS\system32\Macromed\Flash (64-bit):
    Flash64_32_0_0_453.ocx (offset: 12AF6A8)
    NPSWF32_32_0_0_453.dll (offset: 128FBD8)
    pepflashplayer32_32_0_0_453.dll (offset: 15F6C30)

NOTE: Flash32_32_0_0_453.ocx (and Flash64) will always be write protected
    - rename it to Flash32_32_0_0_453.bak
    - save edited copy as Flash32_32_0_0_453.ocx
    - to delete the backup file:
        - properties > security > advanced > delete the "DENY Everyone" permission

Here's what I did:

• Copy the Flash directory (C:\WINDOWS\system32\Macromed\Flash for 32-bit, C:\Windows\SysWOW64\Macromed\Flash for 64-bit) to somewhere where I have write permission;
• Use a hex editor to open Flash.ocx;
• Search for the hexadecimal string 000040463E6F7742 (the timestamp) and replace it with 000000000000F87F;
• Save the file;
• Rename the Flash directory (to avoid permission issues) to Flash.bak or something else;
• Copy the Flash directory with the modified binary to its original location.

I just tested an offline desktop application which had stopped working, and it works again.

Note: the linked page mentions mmc.cfg, but my Flash folder had a mms.cfg file instead; maybe it was a typo, but in any case I added the EOLUninstallDisable=1 line.

Note: In my case, the application using Flash works offline and should present minimal security risks. For continuous usage in a browser, I'd prefer following Tetsujin's recommendation and try a standalone but supported Flash player, such as Newgrounds'.

Solution 2:

There are potential workarounds in other answers below. This answer now probably more closely reflects the 'official stance'.

The Flash plugin itself is responsible for the block, as of 12 Jan.
Microsoft has also time-bombed their own browser, as have many of the other majors, Chrome, Firefox etc.
Apple effectively blocked Flash some time ago.

Adobe have removed all Flash downloads & all major browsers have also blocked it in their latest versions.

From Adobe Flash Player EOL General Information Page

Since Adobe is no longer supporting Flash Player after the EOL Date, Adobe will block Flash content from running in Flash Player beginning January 12, 2021 to help secure users’ systems. Flash Player may remain on the user’s system unless the user uninstalls it.

As to why it also fails on local content as well as remote web content…

From The Register - That's it. It's over. It's really over. From today, Adobe Flash Player no longer works. We're free. We can just leave

More specifically, what's happened is that Adobe snuck a logic bomb into its Flash software some releases ago that activates on January 12, and causes the code to refuse to render any more content from that date. Adobe has also removed previous versions from its site, and "strongly recommends all users immediately uninstall Flash Player to help protect their systems."

It also seems that Microsoft themselves will time-bomb Flash too. See the announcement at Update on Adobe Flash Player End of Support

Updated April 2021 :
To help keep our customers secure, Microsoft will remove the Flash component from Windows through the KB4577586 “Update for Removal of Adobe Flash Player”.

Beginning in January 2021, Adobe Flash Player will be disabled by default and all versions older than KB4561600 released in June 2020 will be blocked. Downloadable resources related to Adobe Flash Player that are hosted on Microsoft websites will no longer be available.

Note from linked page on Edge/Chromium roadmap -

Flash support/ capability will be complete removed from Chromium. It will no longer be possible to enable Flash Player with Enterprise policy in Chrome 88+.

Solution 3:

Note: this answer contains three separate, alternative approaches to this question. First is to configure Flash so that it still works after 12 Jan 2021 for selected sites - this is the one which I have tested and am currently using. Second is to use alternative browser with built-in Flash support, provided by one of the Flash gaming sites. Third is to use the Flash emulator (currently being in active development) which installs either as a browser extension, or directly on a website with Flash content as Javascript code.

#1. Configure Flash to run after 12 Jan 2021.

To run Flash content after 12 January 2021, you need:

1. an old browser that still supports Flash plugin (and of course the Flash plugin itself)
2. a special configuration file specifying "exception" websites, ie. the addresses where Flash content is allowed to run.

All this is documented on "Adobe Flash Player EOL Enterprise Information Page" (the regular EOL page does not contain that information): https://adobe.com/products/flashplayer/enterprise-end-of-life.html, and in the Flash Player Administration Guide linked from that page.

In short, you need to create a file called mms.cfg which should be located in the following directory, depending on operating system (if the directory does not exist, create it):

• on Linux - /etc/adobe
• on 64-bit Windows - C:\Windows\SysWow64\Macromed\Flash
• on 32-bit Windows - C:\Windows\System32\Macromed\Flash

(of course if you installed Windows in a different directory that C:\Windows, change the paths appropriately)

• on MacOS - /Library/Application Support/Macromedia

To allow Flash content to run, you need to put in the mms.cfg file lines specifying which sites Flash player is allowed to access, in the following form:

AllowListUrlPattern=http[s]://site.domain/

If you want to specify both https and http for a site, you may put two lines for https and http, or you can use the following shortcut:

AllowListUrlPattern=*://site.domain/

(you may also specify more detailed URLs, but usually you'd want to allow the entire sites. More details are in the mentioned Flash Player Administration Guide).

You may also specify something like AllowListUrlPattern=file:/// for local files, although it looks superfluous because Firefox does not support playing local Flash files via Flash plugin anymore (it's the only browser I use, so I can't say anyhting about other ones, sorry), and standalone Flash player (aka Flash Player Projector, which is still available for download here) still runs local files specified by command line or loaded via menu option.

You can also put EOLUninstallDisable=1 into mms.cfg file to suppress prompts to uninstall Flash that are mentioned on the Flash EOL page.

#2. Use a specialized browser.

Y8, a Flash-based gaming website, seems to distribute their own browser that supports Flash. Seems to be a customized Chromium version with integrated Flash support. I haven't tried it. It can be downloaded here.

Other gaming sites, such as Newgrounds and Kongregate, also seem to provide their own Flash players, but they are both Windows-only applications and probably work only with the site they are designed for (again, I didn't test them as well). Y8's browser seems to be a more general solution.

Update: from what is written on the Newgrounds forum, their player uses the original Flash ActiveX control so it requires the mms.cfg file anyway. Newgrounds switched to using Ruffle (see below). Kongregate still advertises their player.

#3. Use the Flash emulator.

There's also a Flash emulator called Ruffle which is installed either as browser extension, or by the website owner, on a web page with Flash content as Javascript code (in this case it requires no additional installations on the browser side). Some Flash-based sites, like Armor Games, switched to use it. But it's still at early stages of development and runs only some Flash content. However, it has a chance to be a solution that will replace Flash in the future while preserving the existing Flash applications.

Solution 4:

You can open Flash (URLs and local files) in the official standalone players called "Flash Player projector content debugger" and "Flash Player projector".

Currently, you can download them here: https://www.adobe.com/support/flashplayer/debug_downloads.html

In case this link stops working, they are also here, here, and probably here. Or do a web search for the following file names:

flashplayer_32_sa.exe
flashplayer_32_sa_debug.exe
flash_player_sa_linux.x86_64.tar.gz
flash_player_sa_linux_debug.x86_64.tar.gz
flashplayer_32_sa.dmg
flashplayer_32_sa_debug.dmg