Hi,
I have been having a lot of trouble establishing good communication with a USB Serial Device.
After researching, I have noticed that on all computers where I have the same problem, Avast is installed.
In the USB device driver-stack aswSnx.sys appears on top. If I uninstall avast, all issues disappear.
I would like to know if there is a smart way to disable this driver via avast’s UI.
Thanks for the support.
It is an essential Avast driver (aswSnx.sys’s description is “avast! Virtualization Driver”) and as such no real way build into Avast to disable it.
See https://www.bleepingcomputer.com/startups/aswSnx.sys-27018.html and https://www.freefixer.com/library/file/aswSnx.sys-68131/
What you could try in the Avast User Interface, Menu > Settings > General > Troubleshooting, to disable would be to disable the Enable hardware-assisted virtualisation option. Which I’m thinking would possibly remove any conflict, though I’m unsure why it would be involved with “communication with a USB Serial Device.”
What is/does this USB serial drive do ?
Hi David,
Thanks for your answer.
Before creating this post I tried what you are suggesting, but it didn’t work.
I’m connecting a Thingmagic RFID module with FTDI chip.
This hardware has been running for many years without any problems over all platforms (windows, Android,…) but the other day a client of my company complained that this hardware was not working for him. Upon investigation, it was concluded that this was the problem. Avast was uninstalled and it worked. I tried same setup installing Avast in my personal computer and result was the same.
Anyway, I think I will also request support from FTDI.
As an Avast User, I’m not sure what else could be the possible cause, if this is an Avast Free installation without the Avast Firewall ?
I will try to draw some attention to your topic.
Hi dpons,
can you please be more specific about communication issues? The target port cannot be opened at all, or some data are missing? What SW are you using to communicate and what OS?
Thank you.
Can you please also upload kernel dump, from situation when your serial port communication is not working?
You can use this tool to generate kernel memory dump if you have Windows 8 or later: http://public.avast.com/~hnanicek/livedump.zip
Use the following command line to create the dump file: livedump.exe kernel c:\serial_port_memory.dmp
Please upload the resulting .dmp file using Avast FTP : https://support.avast.com/en-eu/article/FTP-file-upload
Thank you