If your SMS 2.0 client install failed, and ZAK was installed, use regedt32 to navigate to:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment

Record the string values of the following Value Names:

TMP and TEMP

Delete the above Value Names.

On the Edit menu, Add Value names TMP and TEMP as type REG_EXPAND_SZ entries and enter the string values that you had recorded.

Shutdown and restart Windows NT prior to installing the SMS 2.0 client.