When submitting a job or setup, a user may encounter a pop up window that reads, "Unable to evaluate date."

Unable to evaluate date means that JAMS is unable to evaluate the custom date definition defined either in the Scheduled Date or Except For field of a Job, Setup, or Setup Job.  

Normally users see this when typing in incorrect information into one of those fields and JAMS is unable to evaluate the date.  

This can also occur if a Custom Date Definition is defined, however there are not enough dates present in the future to evaluate the custom calendar.

To evaluate each date the 'ConvertTo-date' cmdlet can be used to evaluate the Custom Date Definition, if users have many of these custom dates defined, a simple PowerShell script can be used to evaluate each one.

### Import the JAMS module
Import-Module JAMS


### Define our JAMS provider drive
New-PSdrive JD JAMS JAMSServerName

CD JD:\Dates


### Define an array to hold all of the dates
$dates = @()


### Get all the custom dates
$dates = Get-ChildItem 


### For each date loop through, write out the date and evaluate it.
### Valid dates will return the next closest date on its calendar, invalid will return an error.

ForEach($date in $dates){

    Write-Host "The date is:"$date
    ConvertTo-date $date.name -verbose
    
    }

If one of the date definitions returns an error "Unable to evaluate date", then modify the date in the Dates shortcut to include at least one date in the past, and one in the future.  JAMS must have this condition in order to evaluate the custom date properly.