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GetLastError=126 4.20.3

Hi Guys

I seem to be having multiple issues with opening and using UE4 on my new PC. I keep getting similar errors in all of my crash logs:

LogWindows: Failed to load 'aqProf.dll' (GetLastError=126) LogWindows: File 'aqProf.dll' does not exist LogWindows: Failed to load 'VSPerf140.dll' (GetLastError=126) LogWindows: File 'VSPerf140.dll' does not exist LogWindows: Failed to load 'VtuneApi.dll' (GetLastError=126) LogWindows: File 'VtuneApi.dll' does not exist LogWindows: Failed to load 'VtuneApi32e.dll' (GetLastError=126) LogWindows: File 'VtuneApi32e.dll' does not exist

I also had an error where my prerequisites failed: error code LS-0019-IS-0001

My PC Specs: CPU - AMD Threadripper 1920x GPU - GTX 1080Ti RAM - 32GB OS - Windows 10 64 bit

Unsure what the GetLastError=126 means and after looking on multiple forums I've been unable to track down a solution? Sometimes I can't open a UE4 file at all and when I can it either crashes, or crashes on the lightbuild. I have tried cleaning Swarm Cache as well as validating it, I have tried updating my OS and doing a clean install of my graphics drivers, I have tried completely removing Epic Games Launcher/UE4 and doing a clean install.

This is quite an urgent one for me as I'm currently unable to work on live jobs, so any help would be great.

Thanks guys!

link text

Product Version: UE 4.20
myproject.log (29.4 kB)
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asked Oct 19 '18 at 06:15 AM in Using UE4

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Steven Bracki
21 1 2

avatar image meetakshay99 Dec 20 '18 at 12:21 PM

Did you get this issue resolved? I too am getting it.

avatar image Steven Bracki Jan 12 '19 at 02:05 PM


Apologies for the late response, unfortunately I didn't manage to find a fix for this issue. I actually found that I couldn't even play Battlefield V and I have now sent the PC back to the supplier for a new replacement.

So if I had any suggestions it would be to try stuff outwith the engine such as different games etc to see if the issue is causing problems else where.


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