JSWED failing to launch after a recent Windows 11 update

[jetsetdanny]

A recent Windows 11 update - I believe it's the "2026-03 Update (KB5086672) (26200.8117)" to be precise - makes JSWED (all versions, I believe, I've checked the 2.3.7 and the 2.2.9 ones) fail to launch. When you try to launch the program, you get this error message:

I contacted John Elliott about it and he very kindly responded quickly, explaining that _fmode_dll appears to be part of the Microsoft CRT library and that looking at the dependencies of JSWED, this seems to refer to CRTDLL.DLL in particular.

John told me that the discussion at this link:

https://techcommunity.microsoft.com/discussions/windowsinsiderprogram/windows-11-build-26200-8116-broke-system-dll-crtdll-dll/4508785

seems to suggest that retrieving an earlier version of CRTDLL.DLL might help.

 

I have copied the CRTDLL.DLL file from an old laptop running on Windows 10 and I substituted with it the current file of the same name in the folders: C:\Windows\SysWOW64\ and C:\Windows\WinSxS\x86_microsoft-windows-crtdll_31bf3856ad364e35_10.0.26100.1_none_82a9fe5e3ade4a14\.

 

You need to substitute the current file in the C:\Windows\SysWOW64\ or else JSWED won't launch. I'm not sure about the one in the C:\Windows\WinSxS\x86_microsoft-windows-crtdll_31bf3856ad364e35_10.0.26100.1_none_82a9fe5e3ade4a14\ folder (I first substituted the CRTDLL.DLL file in this particular folder and JSWED still wouldn't launch. It only started working after I substituted the file in C:\Windows\SysWOW64\, so I can say with a 100% certainty that this latter substitution is critical; I wouldn't know about the former).

 

If anyone faces the same problem, the CRTDLL.DLL file from my old Windows 10 laptop that has worked for me is attached to this message. In order to make the swap, you will need to take ownership of the files (and perhaps also folder/s) in question from TrustedInstaller. This link explains how to do it: https://www.google.com/search?q=you+require+permission+from+trustedinstaller+to+make+changes+to+this+file+windows+11&sca_esv=e926bb0053f95734&rlz=1C1CHBF_enUS820US820&sxsrf=ANbL-n6csLu1fdWc35Al3F1HC01pQzzddw%3A1776297342361&ei=fiXgacDYFdOqwbkPhbC32A0&biw=1920&bih=945&oq=you+require+permission+from+trustedinstaller+to+make+changes+to+this+file&gs_lp=Egxnd3Mtd2l6LXNlcnAiSXlvdSByZXF1aXJlIHBlcm1pc3Npb24gZnJvbSB0cnVzdGVkaW5zdGFsbGVyIHRvIG1ha2UgY2hhbmdlcyB0byB0aGlzIGZpbGUqAggCMgoQABhHGNYEGLADMgoQABhHGNYEGLADMgoQABhHGNYEGLADMgoQABhHGNYEGLADMgoQABhHGNYEGLADMgoQABhHGNYEGLADMgoQABhHGNYEGLADMgoQABhHGNYEGLADMg0QABiABBiKBRhDGLADSOYSUABYAHABeAGQAQCYAQCgAQCqAQC4AQPIAQCYAgGgAgWYAwCIBgGQBgmSBwExoAcAsgcAuAcAwgcDMi0xyAcEgAgB&sclient=gws-wiz-serp .

 

Good luck and please let me know if this was helpful if you run into the same problem! 🙂 

 

crtdll.dll

[Spider]

Thanks for the diagnosis and solution.

Before I read the topic, and just saw the title my first thought was "try to run it in compatibility mode, W7 ideal probably" but I see its more involved than that.