Many of our enterprise users have reported problems running the X12ARIMA functionality (e.g. seasonal adjustment, etc.) on their work computer.
X12ARIMA does not work on my work machine
By default, NumXL installer program places all files in a sub-folder under %AppData% (i.e. c:\users\<username>\AppData\Roaming\NumXL). This is a common practice for installing software on a per-user basis and does not require elevated administrative permission for installation.
In many environments, the MIS/IT folks implemented strict software restriction policies for their users' %AppData% folder (and sub-folders) to prevent potentially harmful programs from running in those folders.
Unfortunately, in such environments with strict software restriction policies for %AppData%, the X12ARIMA programs could not be run and such, render the X12ARIMA functionality inoperable.
We recommend our users to move the installation directory outside the %AppData%, by simply re-installing NumXL, but this time, select a different installation directory (e.g. C:\NumXL) from the default one.