Internet explorer ignores flash mms.cfg settings

14
votes

I have the following mms.cfg in

  • %localappdata%\Google\Chrome\User Data\Default\Pepper Data\Shockwave Flash\System\mms.cfg
  • %localappdata%\Microsoft\Edge\User Data\Default\Pepper Data\Shockwave Flash\System\mms.cfg
  • %windir%System32\Macromed\Flash\mms.cfg
  • %windir%\SysWOW64\Macromed\Flash\mms.cfg
EOLUninstallDisable=1
SilentAutoUpdateEnable=0
EnableAllowList=1
AutoUpdateDisable=0
AllowListUrlPattern=http://localhost/flash/
ErrorReportingEnable=1
EnableInsecureLocalWithFileSystem=1

With this after I set my PC date to something in 2021. I'm able to run Flash in

  • Chrome - Which uses the config in %localappdata%\Google\Chrome\User Data\Default\Pepper Data\Shockwave Flash\System\mms.cfg
  • Edge Chromium - Which uses the config in %localappdata%\Microsoft\Edge\User Data\Default\Pepper Data\Shockwave Flash\System\mms.cfg
  • Firefox - %windir%System32\Macromed\Flash\mms.cfg

Based on my understanding IE11 should be using the one from %windir%System32\Macromed\Flash\mms.cfg but for whatever reason it seems like it's ignoring it and the settings in this file have no effect and flash is still disabled. enter image description here

Just to be on the 100% sure that IE uses that config file I've ran ProcMon and it seems like IE is actually opening the file as you can see in the picture. enter image description here

My question is why is internet explorer ignoring this? And what can I do about it? Other useful info:

  • Firefox and Chromium browsers use 32.0.0.433
  • IE11 uses 32.0.0.387 which is the windows embedded version of flash.
  • Tested on
    • Windows 10 Pro 10.0.18362
    • Windows 10 Pro 10.0.19041
    • Windows 10 Home 10.0.18362
  • I took Flash player version 32.0.0.330 from an older version of Windows and I didn't even get the EOL behavior. This leads me to believe that this is a FP version issue and that version 32.0.0.387 which is distributed by MS might not support AllowListUrlPattern.

Things I've tried and didn't work include:

  • Restarting the machine
  • Setting the encoding of the .cfg to UTF-8.
3
windowsinternet-explorerflashwindows-10internet-explorer-11
I tried to test the issue on my side and found that when I try to modify the system date then site which contains flash content not able to match the certificates and it is not loading the contents. Browser also shows the warning that date and time are not correct. After some try system date and time get reset to the current date and time by itself within few seconds of modification. I want to conform with you how did you check and verify that above settings has applied or not. I noticed that Flash player settings manager looks little bit different then I seen it in other examples. - Deepak-MSFT
@Deepak-MSFT I have encountered the behaviors you're describing. The certificates problem occurs only on https, I'm running a local server and using http://localhost/flash. And the date reverting is something I'm experiencing on Windows Sandbox I have another questions on SU here, this does not happen on my actual machine. - Bobby Tables
On my machine IE is using Flash version 32.0.0.330 Can you please inform us how did you check whether the settings from file has been applied or not? Does the same setting works for the current date? - Deepak-MSFT
@Deepak-MSFT With AllowListUrlPattern=http://localhost/flash/ flash continues to work after setting the date to something in 2021, IE is the only one which still exhibits the EOL behavior which is not working and showing the flash logo with an info icon - Bobby Tables
I unchecked the Synchronized with an internet time server option and it helped to modify the future date. After that I noticed that it shows the flash logo with info icon in other browsers but IE still works on my side. It works with any URL. You can notice that I am accessing the example from internet. See here - Deepak-MSFT

3 Answers

7
votes

I tested this on Windows 10 Enterprise 10.0.19041 and Flash Player 32.0.0.387 with same results.

I then ran Windows updates which installed Flash Player 32.0.0.445. https://support.microsoft.com/en-us/help/4580325/security-update

This version respected mms.cfg settings as expected.

My mms.cfg was placed in %windir%\SysWOW64\Macromed\Flash and %windir%\System32\Macromed\Flash

and it looks like this:

EOLUninstallDisable=1
EnableAllowList=1
AllowListUrlPattern=*://*.mydomain.com/
AllowListUrlPattern=*://localhost/
AllowListUrlPattern=*://localhost:5311/

Also, having played around with different dates I've determined the cut off date to be 01/12/2021.

3
votes

Take a loot at article here https://community.adobe.com/t5/flash-player/ie-11-ignores-allowlisturlpattern-in-mms-cfg/td-p/11426041?page=1

Basically, try change the properties names:

  • EnableAllowList into EnableWhiteList
  • AllowlistPreview into WhitelistPreview
  • AllowListUrlPattern into WhitelistUrlPattern
1
votes

I was having the same problem in IE 11 and found the answer at the this page.

In short, using the EnableWhitelist, WhitelistPreview, WhitelistUrlPattern flags instead of EnableAllowList, AllowListPreview, AllowListUrlPattern in the mms.cfg file worked for me.

My mms.cfg file is in below path:

C:\Windows\SysWOW64\Macromed\Flash

Thanks