I am trying to convert a string value to a Datetime value with powershell, but I getting this error:
Excepción al llamar a "ParseExact" con los argumentos "3": "No se puede reconocer la cadena como valor DateTime válido."
En línea: 6 Carácter: 1
+ $CertDate = [DateTime]::ParseExact("$Cert", 'MMM-d-HH:mm:ss-yyyy', $n ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : FormatException
This is my code:
$certificatePath = "C:Usersusercertificate.pem"
$opensslPath = "C:Program FilesOpenSSL-Win64binopenssl.exe"
$Cert = & $opensslPath x509 -in $certificatePath -noout -enddate
$Cert = $Cert.split("=")[1]
$Cert = $Cert.replace(" ","-")
$Cert = $Cert.replace("--","-")
$Cert = $Cert.replace("-GMT","")
$CertDate = [DateTime]::ParseExact("$Cert", 'MMM-d-HH:mm:ss-yyyy', $null)
$CurrentDate = Get-Date
$DateTime = $CertDate - $CurrentDate
$Date = $DateTime.Days
The output of the variable $cert is:
PS C:WINDOWSsystem32> $Cert
Oct-8-11:05:03-2025
And the variable $Cert is a String Type:
PS C:WINDOWSsystem32> $cert.GetType()
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True String System.Object
The $Cert output match with the format indicated in the ParseExact: ‘MMM-d-HH:mm:ss-yyyy’
Any idea of what I am doing wrong?
Thanks and BR!
Tried different formts and doesn’t worked
4
Assuming there are no invisible characters that could be causing this issue, by simply changing the Provider argument from $null to InvariantCulture the issue should be solved.
& {
$Cert = 'Oct-8-11:05:03-2025'
[System.Threading.Thread]::CurrentThread.CurrentCulture =
[cultureinfo]::GetCultureInfo('es-AR')
[DateTime]::ParseExact($Cert, 'MMM-d-HH:mm:ss-yyyy', [cultureinfo]::InvariantCulture)
# Correctly parses into: `miércoles, 8 de octubre de 2025 11:05:03`
}
In ParseExact Remarks section you can read the following:
If provider is
null, the CultureInfo object that corresponds to the current culture is used.
In Spanish culture a month in the MMM format would end with a ., i.e.: Oct.. This is why using $null fails to parse and also this is proven by, if you add the . it parses correctly:
& {
# With the `.` after `Oct` this parses corretly in Spanish culture
$Cert = 'Oct.-8-11:05:03-2025'
[System.Threading.Thread]::CurrentThread.CurrentCulture =
[cultureinfo]::GetCultureInfo('es-AR')
[DateTime]::ParseExact($Cert, 'MMM-d-HH:mm:ss-yyyy', $null)
}
Thanks for all the help!
Replacing “$null” to “[cultureinfo]::InvariantCulture” solved my issue.
BR,