Re: cannot install vsphere webclient

The admin@system-domain password is what was entered during setup of vCenter.  Do you remember what you entered?  If not, you could reset the password manually.  You did not mention if it was a vCenter Appliance or install on a Windows server.  Here are directions for both.

To reset the SSO administrator password on a Windows server:

1. Login as an administrator to the vCenter SSO server.
2. Click Start > Run, type cmd, and click OK. The Command Prompt window opens.

3. Navigate to the directory SSOInstallDirectory\utils. By default, the installation directory is  C:\ProgramFiles\VMware\Infrastructure\SSOServer.

4. Run this command:  rsautil reset-admin-password
5. Enter the master password when prompted.
6. Note: This is the password selected for the SSO administrator during the SSO installation. If you have changed your SSO administrator password later, the master password is still the original one chosen.
7. Enter the SSO administrator name for which you want to reset the password. For example, admin.
8. Enter the new password for the user and then confirm it a second time.

You should see the message Password reset successfully.

Log in as root to the vCenter server Appliance.

1. From the command line, navigate to /usr/lib/vmware-sso/utils directory.
2. Run this command:  ./rsautil reset-admin-password
3. Enter the master password when prompted.
4. Note: By default, this is the root password.
5. Enter the SSO administrator name for which you want to reset the password. For example, admin.
6. Enter the new password for the user and then confirm it a second time.

You should see the message Password reset successfully.

Here is a link to the Configuring vCenter Single Sign On.