New Post: Specified cast is not valid. (at

I have a few random systems that throw the following error for an application install script. One win 7 and one win 8 all other systems seem to install fine.

Specified cast is not valid. (at<scriptBlock>.
c:....AppDeployToolkitMain.ps1:
line 1009
at Get-InstalledApplication

at Remove-MSIApplications,
c:....AppDeployToolkitMain.ps1:
line 1235

Any help or suggestions would be appreciated