Please be a bit more specific about what you mean by “crashing.”
Also, please identify which version of Windows you have, including service pack. You can find this information by right-clicking “Computer” or “My Computer” and selecting “Properties.”
Do you mean that you receive an error message that references sshnas.dll when Windows first starts? If so, please provide the complete text of the message.
Assuming this is what you mean, the problem is that your antivirus software has deleted or quarantined a file named SSHNAS.DLL, which is known to be malware, but has left behind the Windows registry information that is attempting to start the malware.
As a precaution in case you have additional malware, download, install, update, and run full scans with both of these free scanning tools:
Don’t select the option to install the free trial of the Premium or Pro version. Don’t run the scans simultaneously. They may take a while, so start one up and then go do a non-computer chore for a while.
If the scans don’t fix the problem (and they may not, because the actual malware file has already been dealt with), then download and run Autoruns. Click the “Logon” tab and look in the “Image Path” column for the file named in your error message. If it isn’t shown in the Logon tab, click the “Everything” tab and use the File > Search tool.
Once you find the line with the offending file, either “Delete” it or (if you want to be safer) uncheck it. The latter prevents the line from being executed but you can reactivate it later by replacing the check mark.
If you mean something else, please explain.