Virtual Machine edit settings fail with error "object is not an instance of declaring class and java.lang.ClassCastException@17f42f3"
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Virtual Machine edit settings fail with error "object is not an instance of declaring class and java.lang.ClassCastException@17f42f3"

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Article ID: 318736

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Updated On:

Products

VMware vCenter Server

Issue/Introduction

Symptoms:
  • Unable to edit VM settings on vSphere Client (HTML5 Client)
  • We get following error: object is not an instance of declaring class or java.lang.ClassCastException@17f42f3


Environment

VMware vCenter Server 6.5.x
VMware vCenter Server 7.0.x
VMware vCenter Server 6.7.x

Resolution

This issue is resolved in :
  • vCenter 7.0 U3
  • vCenter 6.7 U3p
  • vCenter 6.5 U3t


Workaround:
1. Power off the Virtual Machine that has the problem.

2. Connect to the ESXi host where the VM is running through SSH. For more information, see 
Using ESXi Shell in ESXi 5.x, 6.x and 7.x (2004746)

3. Browse to the virtual machine directory using the below command:
# cd /vmfs/volumes/<datastore>/<VM_name>

4. Edit the virtual machine configuration file <VM_name>.vmx using a text editor (vi). For more information, see Editing files on an ESXi host using vi (1020302) to change the value of the parameter "toolsInstallManager.lastInstallError" to be set to "0"
Example:   toolsInstallManager.lastInstallError = "0"

5.Run the below command on the ESXi host to identify the vmid of the affected VM.
# vim-cmd vmsvc/getallvms

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6. Run the below command to reload the VM config.
# vim-cmd vmsvc/reload <Vmid>
Example: # vim-cmd vmsvc/reload 14

7. Re-login to vSphere Client and VM edit settings will work successfully.

Note: If the above workaround is not possible, use ESXi Host Client or vSphere Web Client (Flash) to edit the VM settings. For more information see the below link.
Start the VMware Host Client and Log In