Applications virtualized with ThinApp fail to open some files with an Access is Denied error message when the sandbox is on the network location and the user does not have WRITE_DAC permission for that location. To overcome this issue, DisableWriteDAC parameter is used.

When DisableWriteDAC=1, while opening or creating files in the sandbox, WRITE_DAC permission is not checked during ThinApp runtime.

You can add this parameter to the General Purpose Parameters section of Package.ini.