Fast User Switching -- Computer Hangs

[ohso]

Windows XP Pro+SP3+updates, 32b, 2 GB memory
1 admin acct, 3 limited user accts
SDwAV 6.1.0.447

I have in previous posts pointed out problems switching from a limited user acct to the admin acct. The computer freezes/hangs.

In Services, fast user switching is set to auto.

A Microsoft support page (that I just read for the first time) points out another requirement.
Start -> CP -> User Accts
User Accts -> Change the way users log on or off
Both "Use the welcome screen" and "Use fast user switching" must be checked. Since I haven't seen this screen before, I'm guessing it must be the dafault.

<http://www.blackviper.com/WinXP/Services/Fast_User_Switching_Compatibility.htm>
This page describes some dependencies of fast user switching. Terminal Services and Remote Procedure Call are needed. I turned both to auto.

Here is where the experiment begins.
It must be done just like this.

Restart the computer.
Log into one of the limited user accts.
Let it load and settle so that it is idle.
Use fast user switching to log out.
Log into the admin acct.

This computer hangs nearly every time.

Is it SD or something else?

[AChen]

Hi Ohso,

This is something we'll have to investigate. We do some tests with this and see if we can recreate this inhouse. Could you try changing the kernel mode to see if this helps? There has been no reports with switching users with build 447 to date.

[ohso]

> Could you try changing the kernel mode to see if this helps?

When "enable kernel compatibility mode" is checked, the computer hangs.
When it is unchecked, it does not.

[Bianca150]

Hmm.. I have other limited account in my XP PRO SP3 PC w/c my kids uses and never had problems like yours, and I'm using SDAV 6.1.0.447 too.

Sometimes it hangs especially if other account have something running still when switching.

Try cleaning up your system then defrag, also perform check disk, it could work.

[ohso]

> Sometimes it hangs especially if other account have something running still when switching.

Absolutely nothing (of the user's) is running at the time of switching user.

> Try cleaning up your system then defrag, also perform check disk, it could work.

It's difficult to understand, from a technical point of view, how that could contribute to a switching user problem. Surely, if that were the case, it would manifest itself in some other ways also. There are no other (obvious) problems with this computer.

But the real point is -- this only happens when SD's kernel compatibility mode is checked.

I need a theory that takes that into account.

[ohso]

> never had problems like yours

Is your kernel compatibility mode checked?
If you have time, do it exactly as below.

> also perform disk check

I just ran disk check, to eliminate possibilities.

(Rt click start, Explore, rt click C, Properties, Tools tab, Check Now, check "automatically fix file system errors", yes to "do it at next start-up," restart.)

It still hangs if kernel compatibility mode is checked.

Further definition: it doesn't hang when fast switching from one limited user acct to another limited acct. Only from a limited user acct to the admin acct.

We do that on this particular computer _every day_.
As a work-around we have to log completely out of the limited acct.
That takes more time, of course, plus the additional time going back into the user acct.
It shouldn't be necessary to have to do this. This is likely a bug.

Revised example:

In the admin acct, open SDwAV and check the kernel compatibility box.
Run ccleaner (or equivalent) in every acct.
Restart the computer.
Log into one of the limited accts.
Start nothing. Let it settle so that it is idle.
Use Win task mgr to assure that nothing is running in this acct.
Use fast user switching to log out.
Log into the admin acct.

The computer hangs if kernel compatibility mode is checked.

[AChen]

Hey Ohso,

Many thanks for all the info. Managed to recreate the problem ;) and have passed it off to the devs for a fix.

Update: Currently testing this with SDv6.5.0.460 beta and will see if the same problem occurs.

[AChen]

After testing with SDv6.5.0.460 beta, the problem is no longer there :D So if you wish to try this version, please let me know.

[ohso]

Thanks for checking this out achen.

I'll pass on the beta since the primary user of this computer probably can't cope with any potential problems.