did an upgrade to .51 the other day and now I can't record MP4s. All other formats record fine. Anyone see this? I get an "attempt to read or write protected memory" error. Everything else seems fine.

to add to this;
I have reinstalled both this version and prior versions of vMix with the same result and error.
I can record in every other (vMix) format no problem.
SFC shows no errors in my OS (W10).
My other video apps record mp4s fine.

Ideas?

Thanks

I have not seen this issue on my setup. Try running a test with a blank canvas and 1 camera to see if recording MP4 works. Maybe change the destination drive as Barney Box Lane suggested to see if it is a permission error. With other formats working without issue that seems strange to me unless you have MP4 going to a different location...

I just resigned myself to recording FFMPEG and converting to mp4. PC was sitting idle with vMix running and vMix crashed.
Event Viewer logged an error report:

Fault bucket 1576053652562377035, type 5
Event Name: CLR20r3
Response: Not available
Cab Id: 0

Problem signature:
P1: vmix64.exe
P2: 20.0.0.51
P3: 5a66c2a1
P4: mscorlib
P5: 2.0.0.0
P6: 59a72025
P7: 2224
P8: 56
P9: N3CTRYE2KN3C34SGL4ZQYRBFTE4M13NB
P10:

Attached files:
\\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERE4E8.tmp.mdmp
\\?\D:\GT - 27 January 2018 - 11-36-36 PM.mp4
\\?\F:\capture - 27 January 2018 - 11-28-49 PM.mp4
\\?\F:\capture - 27 January 2018 - 11-17-25 PM.mp4
\\?\F:\capture - 27 January 2018 - 11-17-21 PM.mp4
\\?\F:\capture - 27 January 2018 - 11-17-08 PM.mp4
\\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERFA17.tmp.WERInternalMetadata.xml
\\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERFA45.tmp.csv
\\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERFA65.tmp.txt

These files may be available here:
C:\ProgramData\Microsoft\Windows\WER\ReportArchive\AppCrash_vmix64.exe_eff1515f4257171a072bd84886cc5435cb2043_00000000_1cbffd90

Analysis symbol:
Rechecking for solution: 0
Report Id: f92e1058-6295-4af8-9b8e-47e39550e548
Report Status: 268435456
Hashed bucket: e7840eecc2ba852ba5df44725beff94b

---

- <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
- <System>
<Provider Name="Windows Error Reporting" />
<EventID Qualifiers="0">1001</EventID>
<Level>4</Level>
<Task>0</Task>
<Keywords>0x80000000000000</Keywords>
<TimeCreated SystemTime="2018-01-28T05:48:14.391917000Z" />
<EventRecordID>2974</EventRecordID>
<Channel>Application</Channel>
<Computer>Sstreamer17</Computer>
<Security />
</System>
- <EventData>
<Data>1576053652562377035</Data>
<Data>5</Data>
<Data>CLR20r3</Data>
<Data>Not available</Data>
<Data>0</Data>
<Data>vmix64.exe</Data>
<Data>20.0.0.51</Data>
<Data>5a66c2a1</Data>
<Data>mscorlib</Data>
<Data>2.0.0.0</Data>
<Data>59a72025</Data>
<Data>2224</Data>
<Data>56</Data>
<Data>N3CTRYE2KN3C34SGL4ZQYRBFTE4M13NB</Data>
<Data />
<Data>\\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERE4E8.tmp.mdmp \\?\D:\GT - 27 January 2018 - 11-36-36 PM.mp4 \\?\F:\capture - 27 January 2018 - 11-28-49 PM.mp4 \\?\F:\capture - 27 January 2018 - 11-17-25 PM.mp4 \\?\F:\capture - 27 January 2018 - 11-17-21 PM.mp4 \\?\F:\capture - 27 January 2018 - 11-17-08 PM.mp4 \\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERFA17.tmp.WERInternalMetadata.xml \\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERFA45.tmp.csv \\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERFA65.tmp.txt</Data>
<Data>C:\ProgramData\Microsoft\Windows\WER\ReportArchive\AppCrash_vmix64.exe_eff1515f4257171a072bd84886cc5435cb2043_00000000_1cbffd90</Data>
<Data />
<Data>0</Data>
<Data>f92e1058-6295-4af8-9b8e-47e39550e548</Data>
<Data>268435456</Data>
<Data>e7840eecc2ba852ba5df44725beff94b</Data>
</EventData>
</Event>

just great, I tell ya! PC seems to be running fine though...

I have tried that, as well as many variations of bit rate, size, frame rate, etc. This particular PC used to be my go-to box! Maybe time to reinstall the OS.....

---

W10 OS reinstall fixed the issue. So its a mystery. Installed last known good version of vMix [20.0.0.27(x64)] and got a trial sub, which I'll use until its expired.

Interestingly, adding the newest BM drivers (10.9.10) has absolutely caused the PC to 1) show a "Decklink Duo requires driver software to be installed" notice, but more interestingly has put the boot up into a Selective Startup mode (msconfig) which if changed to Normal, causes a freeze-up on Restart..though a shutdown and restart works fine. This is not dependent on Fast boot (or not) either.

Go Microsoft! (sarc)