Remote Assistance MSRA can't send mail with thunderbird

Question

Hello,
First, sorry for my poor english.

I'm sure i'm not the only one guy with this issue. Old peoples that ask me for help and use thunderbird can't "now" (since one or tow years) use thunderbird to send the file. It's difficult for old peoples to send to me the invitation file. Many of us doen't understand that they can use a webmal. And they can't find the file in their file system. Some ones can't save the file in a place and refind this place in the webbrowser. Yes, WE are old. And "YOU" will be old one day and YOU will become senile like us.
Since a new version of w10 but i don't know which one, RemoteAssistance can't open the client SMAPI of thunderbird.
There is no communication from MS for this change !!!

I make trace/debugger session in W10-64bit-V19h1 ( it's a little different with 20h2, not the same error !)

I use windbg, procmon, ida. And i see that LoadLibraryA returns "ERROR_INVALID_IMAGE_HASH 577 (0x241) : Windows cannot verify the digital signature for this file". And it returns that because CI.dll detects a "wrong" certificat (I think that). I see in the stack a call to CI.dll!CipReportAndReprieveUMCIFailure. I see rapidely that in 20h2 the stack is different but issue is there.
It seems that a new security level for RemoteAssistance was introduce in a "new" (2018/2019) versions of w10.

RemoteAssistance uses a SMAPI dll, mozmapi32-inuse.dll in the case of Thunderbird as client mail.
This dll is well signed. But it seems to me that MS, for security reason, imposes a certificat with a "better" level and blocks other certificats when using RemoteAssistance (msra.exe).

If I change the client\mail to "hmmapi.dll" (the original item), the site html outlook.com is open. But this hmmapi.dll seems to be not signed ( no digital signature in properties in explorer). Does it mean that OS doesn't check certificat for MS program ? So, why it check for tunderbird? Complex ! There is no change in thunderbird about the smapi dll.

If a use an old mail client, "Windows Live/mail" coming in W7, and its Smapi.dll file, the program Winmail.exe is launched. And if i modify the path of this program with "Thunderbird -compose ..." then i can send the file. But Smapi.dll seems to wait for a event that i can't identify and, so, RA fails. Smapi.dll adds "-embedding" into the command line and i can't "make" the necessary work for that.

If someone can test and explain, and also show me how to use thunderbird with MSRA, i will be happy.

Notes :

• i don't need a workaround, i wrote a powershell script for "open msra/sending file" for the novices that i help.
• we shouldn't be confused with default programs "mailto::" which is an other thing even if there is a "little link".
• Quick Assist in not a good reply, nor Teamviewer...

See you soon, thank you.

PS : this form ask to me to choose a tag that identifies the good service? But the list is poor or i don't understand somethink. Oh, yes, i am OLD ! i know that remote desktop client "MSTSC.exe" is not "MSRA.exe". But what can i enter to this stupid form "Tags"?

Answer 1

Hey @noel blanc

Your issue is relate to third-party program and not related with Remote Desktop, which is not in my scope. Sorry I can not provide you useful information.

Best regards
Karlie

Answer 2

hello KarlieWeng,
I understand that MSRA.exe is not the same as MSTSC.exe.
Yes it's a third-party program.
But not only ! MSRA is build by MSFT and it's MSRA that can't load the smapi-third-party dll because of some security.
Why can't i find/know informatio about this modificatio of security?

I post in many forum. You are the only one which want to reply to me. You are a very kind guy.
Thank you for your post.