Getting Error: 102 Invalid Class in WMI-based Service

Last Modified

Mon Apr 15 20:37 GMT 2019

Description

  • Monitored devices in N-able N-central are getting an error 102 Invalid Class on WMI-based Service

Environment

  • N-able N-central

Solution

  • This is generally and issue with the Service Details using the incorrect Property, or WMI not having the class in question.
    • This would be resolved by correcting the Service Details options (if available, service dependent) or by correcting WMI.
    • For troubleshooting issues regarding 102 invalid class, you need to check if the class exist using the command below:
WMIC /namespace:\\root\cimv2 PATH <wmi class> GET /value
  • Example:
C:\Windows\System32\> WMIC /namespace:\\root\cimv2 PATH Win32_BIOS GET /value
  • Sample Output: 
BiosCharacteristics={7,9,11,12,15,16,19,23,24,25,26,27,28,29,32,33,39,40,41,42,43,50,57,58,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79}
BIOSVersion={"DELL   - 1072009","BIOS Date: 05/01/14 23:18:57 Ver: A06.00 "}
BuildNumber=
Caption=BIOS Date: 05/01/14 23:18:57 Ver: A06.00
CodeSet=
CurrentLanguage=en|US|iso8859-1
Description=BIOS Date: 05/01/14 23:18:57 Ver: A06.00
IdentificationCode=
InstallableLanguages=1
InstallDate=
LanguageEdition=
ListOfLanguages={"en|US|iso8859-1"}
Manufacturer=Dell Inc.
Name=BIOS Date: 05/01/14 23:18:57 Ver: A06.00
OtherTargetOS=
PrimaryBIOS=TRUE
ReleaseDate=20140501000000.000000+000
SerialNumber=JJ3NH12
SMBIOSBIOSVersion=A06
SMBIOSMajorVersion=2
SMBIOSMinorVersion=7
SMBIOSPresent=TRUE
SoftwareElementID=BIOS Date: 05/01/14 23:18:57 Ver: A06.00
SoftwareElementState=3
Status=OK
TargetOperatingSystem=0
Version=DELL   - 1072009
  • In the example above, we query the WMI class Win32_BIOS and it shows all the properties of that class.
  • You can also query for specific properties using this command below:
C:\Windows\System32\> WMIC /namespace:\\root\cimv2 PATH Win32_BIOS GET Caption, Description, Manufacturer, Name /value
Caption=BIOS Date: 05/01/14 23:18:57 Ver: A06.00
Description=BIOS Date: 05/01/14 23:18:57 Ver: A06.00
Manufacturer=Dell Inc.
Name=BIOS Date: 05/01/14 23:18:57 Ver: A06.00
  • Another example where the service throws 102 Invalid Class
  • Sample Error:
102 Invalid class when process matrix 0 WQL = Select ReplayQ, CopyQ, Status, Name From NCentral_DAGCopyStatus Where Name="First-Mailboxdatastore\\GSS-EXC-MDB01" 
  • In this error, the WMI class is NCentral_DAGCopyStatus.
  • In some cases, WMI class exists but the instance or the properties does not exist.
  • You may try to use the command below to check if the property exist
C:\Windows\system32>wmic /namespace:\\root\cimv2\ N-able N-centralPATH NCentral_DAGCopyStatus GET Name /value
  • By default, the namespace should always be in  “root\cimv2”.
  • There are also other namespaces like “root\SecurityCenter” for monitoring 3rd party AV.
  • In this example, the WMI class is located on another namespace “root\cimv2\Ncentral”.
Output: 
Name=SystemDB\AMSCS-EX01
Name=MAILBOXES\AMSCS-EX01
Name=ARCHIVE\AMSCS-EX01
Name=ArbitrationBS\AMSCS-EX01
  • In the output, it does not show the said property which causing the 102 Invalid Class.