Norton 360 alerts about the suspicious file
sharedhostappsshext.dll and removes it.
sharedhostappsshext.dll file is a part of Parallels Tools installation that provides the Shared Applications functionality and it is not harmful to your virtual machine.
Norton 360 is not optimized to work inside Parallels Desktop virtual machines that causes such false detection.
Parallels suggests to use Kaspersky Internet Security with your virtual machines as it is optimized to work inside virtual machines. To install Kaspersky Internet Security provided with your copy of Parallels Desktop 10 please visit KB 116884
Important: Make sure to uninstall any other 3rd party antivirus/firewall/Internet Security solution before installing Kaspersky Internet Security!
Should you choose not to uninstall Norton 360 and switch to Kaspersky, use the following workaround to recover the removed file and exclude it from detection in future.
In Nortin 360 click on Options
Click Restore & Exclude this file
Click Yes to confirm restoring the file
sharedhostappsshext.dllfile is successfully restored!