SystemParameter sInfo Failing in VB.net

[Mike S.]

I'm using a SystemParameter sInfo call to attempt to manage the screen saver.
All I want to do is modify the ScreenSaveActiv e bit in the registry and have
the OS recognize it (and occasionally set it back to -0-). Theoretically this
should be easy to accomplish through the call shown below. If I trace the
call with SysInternals (si)Registry Monitor I can see the call being made.
Unfortunately in the si QueryValue for the key
HKCU\Software\P olicies\Microso ft\Windows\Cont rol
Panel\Desktop\S creenSaveActive I'm getting a result of BUFOVRFLOW (which I
assume is the trace tool unable to read the value). The value in the registry
does not change.

We do have a forced screen saver GPO applied which I suspect may be causing
the failure. I have checked registry permissions and all is ok on this key.
I've used the SPIF_SENDWININI CHANGE parameter with no luck. The following
call is about as basic as I can get for troubleshooting this problem. Any
ideas?

VB.net 1.1, Win2KPro (and XPPro) Also tried C++6.0 and VB6.0.
VB.net call

Private Declare Function SystemParameter sInfo Lib "user32" _
Alias "SystemParamete rsInfoA" (ByVal uAction As Long, ByVal _
uParam As Long, ByVal lpvParam As Long, ByVal fuWinIni As _
Long) As Long

Private Function SetScreenSaver( ByVal Active As Boolean) As Long
Dim lActiveFlag As Long = 0
If Active = True Then lActiveFlag = 1
Return = SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, lActiveFlag, 0, 0)
End Function
-Mike

[Imran Koradia]

Change all the Longs to Integers. Longs from VB 6.0 convert to Integers in
VB.NET (both are 32-bit integers). That should most likely be the reason for
the failure in VB.NET.

hope that helps..
Imran.

"Mike S." <Mike S.@discussions. microsoft.com> wrote in message
news:41******** *************** ***********@mic rosoft.com...

I'm using a SystemParameter sInfo call to attempt to manage the screen saver. All I want to do is modify the ScreenSaveActiv e bit in the registry and have the OS recognize it (and occasionally set it back to -0-). Theoretically this should be easy to accomplish through the call shown below. If I trace the
call with SysInternals (si)Registry Monitor I can see the call being made.
Unfortunately in the si QueryValue for the key
HKCU\Software\P olicies\Microso ft\Windows\Cont rol
Panel\Desktop\S creenSaveActive I'm getting a result of BUFOVRFLOW (which I
assume is the trace tool unable to read the value). The value in the registry does not change.

We do have a forced screen saver GPO applied which I suspect may be causing the failure. I have checked registry permissions and all is ok on this key. I've used the SPIF_SENDWININI CHANGE parameter with no luck. The following
call is about as basic as I can get for troubleshooting this problem. Any
ideas?

VB.net 1.1, Win2KPro (and XPPro) Also tried C++6.0 and VB6.0.
VB.net call

Private Declare Function SystemParameter sInfo Lib "user32" _
Alias "SystemParamete rsInfoA" (ByVal uAction As Long, ByVal _
uParam As Long, ByVal lpvParam As Long, ByVal fuWinIni As _
Long) As Long

Private Function SetScreenSaver( ByVal Active As Boolean) As Long
Dim lActiveFlag As Long = 0
If Active = True Then lActiveFlag = 1
Return = SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, lActiveFlag, 0, 0) End Function
-Mike

[Mike S.]

Thanks for the quick response Imran!

Actually the code I posted was from one of the tests where I had just
changed those from integers. Unfortunately it didn't make a difference but
I'll post the corrected code below.

Private Declare Function SystemParameter sInfo Lib "user32" _
Alias "SystemParamete rsInfoA" (ByVal uAction As Integer, ByVal _
uParam As Integer, ByVal lpvParam As Integer, ByVal fuWinIni As _
Integer) As Integer

Private Function SetScreenSaver( ByVal Active As Boolean) As Integer
Dim iActiveFlag As Integer = 0
If Active = True Then iActiveFlag = 1
Return SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, iActiveFlag, 0, 0)
End Function

"Imran Koradia" wrote:

Change all the Longs to Integers. Longs from VB 6.0 convert to Integers in
VB.NET (both are 32-bit integers). That should most likely be the reason for
the failure in VB.NET.

hope that helps..
Imran.

"Mike S." <Mike S.@discussions. microsoft.com> wrote in message
news:41******** *************** ***********@mic rosoft.com...

I'm using a SystemParameter sInfo call to attempt to manage the screen

saver.

All I want to do is modify the ScreenSaveActiv e bit in the registry and

have

the OS recognize it (and occasionally set it back to -0-). Theoretically

this

should be easy to accomplish through the call shown below. If I trace the
call with SysInternals (si)Registry Monitor I can see the call being made.
Unfortunately in the si QueryValue for the key
HKCU\Software\P olicies\Microso ft\Windows\Cont rol
Panel\Desktop\S creenSaveActive I'm getting a result of BUFOVRFLOW (which I
assume is the trace tool unable to read the value). The value in the

registry

does not change.

We do have a forced screen saver GPO applied which I suspect may be

causing

the failure. I have checked registry permissions and all is ok on this

key.

I've used the SPIF_SENDWININI CHANGE parameter with no luck. The following
call is about as basic as I can get for troubleshooting this problem. Any
ideas?

VB.net 1.1, Win2KPro (and XPPro) Also tried C++6.0 and VB6.0.
VB.net call

Private Declare Function SystemParameter sInfo Lib "user32" _
Alias "SystemParamete rsInfoA" (ByVal uAction As Long, ByVal _
uParam As Long, ByVal lpvParam As Long, ByVal fuWinIni As _
Long) As Long

Private Function SetScreenSaver( ByVal Active As Boolean) As Long
Dim lActiveFlag As Long = 0
If Active = True Then lActiveFlag = 1
Return = SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, lActiveFlag, 0,

0)

End Function
-Mike

[Imran Koradia]

Try using this instead:

Private Const SPI_SETSCREENSA VEACTIVE As Integer = 17
Private Const SPIF_SENDWININI CHANGE As Integer = &H2
Private Const SPIF_UPDATEINIF ILE As Integer = &H1

Return SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, iActiveFlag, _
0, SPIF_SENDWININI CHANGE Or SPIF_UPDATEINIF ILE)
hope that helps..
Imran.

"Mike S." <Mike S.@discussions. microsoft.com> wrote in message
news:41******** *************** ***********@mic rosoft.com...

I'm using a SystemParameter sInfo call to attempt to manage the screen saver. All I want to do is modify the ScreenSaveActiv e bit in the registry and have the OS recognize it (and occasionally set it back to -0-). Theoretically this should be easy to accomplish through the call shown below. If I trace the
call with SysInternals (si)Registry Monitor I can see the call being made.
Unfortunately in the si QueryValue for the key
HKCU\Software\P olicies\Microso ft\Windows\Cont rol
Panel\Desktop\S creenSaveActive I'm getting a result of BUFOVRFLOW (which I
assume is the trace tool unable to read the value). The value in the registry does not change.

We do have a forced screen saver GPO applied which I suspect may be causing the failure. I have checked registry permissions and all is ok on this key. I've used the SPIF_SENDWININI CHANGE parameter with no luck. The following
call is about as basic as I can get for troubleshooting this problem. Any
ideas?

VB.net 1.1, Win2KPro (and XPPro) Also tried C++6.0 and VB6.0.
VB.net call

Private Declare Function SystemParameter sInfo Lib "user32" _
Alias "SystemParamete rsInfoA" (ByVal uAction As Long, ByVal _
uParam As Long, ByVal lpvParam As Long, ByVal fuWinIni As _
Long) As Long

Private Function SetScreenSaver( ByVal Active As Boolean) As Long
Dim lActiveFlag As Long = 0
If Active = True Then lActiveFlag = 1
Return = SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, lActiveFlag, 0, 0) End Function
-Mike

[Mike S.]

Still no luck. The call looks like it's going through to user32.dll, but it's
not executing completely or properly. I am getting a return value of 0.

When I look at the registry trace I'm seeing a successful "OpenKey" request
to HKCU\Software\P olicies\Microso ft\Windows\Cont rol Panel\Desktop. The next
entry "QueryKey" HKCU\Software\P olicies\Microso ft\Windows\Cont rol
Panel\Desktop\S creenSaveActive fails with a result of BUFOVRFLOW. The third
and final trace entry of "CloseKey"
HKCU\Software\P olicies\Microso ft\Windows\Cont rol Panel\Desktop completes
successfully.

"Imran Koradia" wrote:

Try using this instead:

Private Const SPI_SETSCREENSA VEACTIVE As Integer = 17
Private Const SPIF_SENDWININI CHANGE As Integer = &H2
Private Const SPIF_UPDATEINIF ILE As Integer = &H1

Return SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, iActiveFlag, _
0, SPIF_SENDWININI CHANGE Or SPIF_UPDATEINIF ILE)
hope that helps..
Imran.

"Mike S." <Mike S.@discussions. microsoft.com> wrote in message
news:41******** *************** ***********@mic rosoft.com...

I'm using a SystemParameter sInfo call to attempt to manage the screen

saver.

All I want to do is modify the ScreenSaveActiv e bit in the registry and

have

the OS recognize it (and occasionally set it back to -0-). Theoretically

this

should be easy to accomplish through the call shown below. If I trace the
call with SysInternals (si)Registry Monitor I can see the call being made.
Unfortunately in the si QueryValue for the key
HKCU\Software\P olicies\Microso ft\Windows\Cont rol
Panel\Desktop\S creenSaveActive I'm getting a result of BUFOVRFLOW (which I
assume is the trace tool unable to read the value). The value in the

registry

does not change.

We do have a forced screen saver GPO applied which I suspect may be

causing

the failure. I have checked registry permissions and all is ok on this

key.

I've used the SPIF_SENDWININI CHANGE parameter with no luck. The following
call is about as basic as I can get for troubleshooting this problem. Any
ideas?

VB.net 1.1, Win2KPro (and XPPro) Also tried C++6.0 and VB6.0.
VB.net call

Private Declare Function SystemParameter sInfo Lib "user32" _
Alias "SystemParamete rsInfoA" (ByVal uAction As Long, ByVal _
uParam As Long, ByVal lpvParam As Long, ByVal fuWinIni As _
Long) As Long

Private Function SetScreenSaver( ByVal Active As Boolean) As Long
Dim lActiveFlag As Long = 0
If Active = True Then lActiveFlag = 1
Return = SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, lActiveFlag, 0,

0)

End Function
-Mike

[Imran Koradia]

Ok..I'm officially stumped :-S

One reason for BUFOVRFLOW is that the key does not exist in the registry. On
my machine, I have the ScreenSaveActiv e key under HKCU\Control Panel\Desktop
which is different from whats showing in your registry trace. I'm not sure
if this has got anything to do with that. Its working fine on my machine -
the value changes from 1 to 0 and vice versa correctly.
Any viruses, trojans, etc? Corrupt registry, etc?

Can't think of anything else..sorry.

Imran.

"Mike S." <Mi***@discussi ons.microsoft.c om> wrote in message
news:09******** *************** ***********@mic rosoft.com...

Still no luck. The call looks like it's going through to user32.dll, but it's not executing completely or properly. I am getting a return value of 0.

When I look at the registry trace I'm seeing a successful "OpenKey" request to HKCU\Software\P olicies\Microso ft\Windows\Cont rol Panel\Desktop. The next entry "QueryKey" HKCU\Software\P olicies\Microso ft\Windows\Cont rol
Panel\Desktop\S creenSaveActive fails with a result of BUFOVRFLOW. The third and final trace entry of "CloseKey"
HKCU\Software\P olicies\Microso ft\Windows\Cont rol Panel\Desktop completes
successfully.

"Imran Koradia" wrote:

Try using this instead:

Private Const SPI_SETSCREENSA VEACTIVE As Integer = 17
Private Const SPIF_SENDWININI CHANGE As Integer = &H2
Private Const SPIF_UPDATEINIF ILE As Integer = &H1

Return SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, iActiveFlag, _
0, SPIF_SENDWININI CHANGE Or SPIF_UPDATEINIF ILE)
hope that helps..
Imran.

"Mike S." <Mike S.@discussions. microsoft.com> wrote in message
news:41******** *************** ***********@mic rosoft.com...

I'm using a SystemParameter sInfo call to attempt to manage the screen

saver.

All I want to do is modify the ScreenSaveActiv e bit in the registry and

have

the OS recognize it (and occasionally set it back to -0-).

Theoretically this

should be easy to accomplish through the call shown below. If I trace

the call with SysInternals (si)Registry Monitor I can see the call being made. Unfortunately in the si QueryValue for the key
HKCU\Software\P olicies\Microso ft\Windows\Cont rol
Panel\Desktop\S creenSaveActive I'm getting a result of BUFOVRFLOW (which I assume is the trace tool unable to read the value). The value in the

registry

does not change.

We do have a forced screen saver GPO applied which I suspect may be

causing

the failure. I have checked registry permissions and all is ok on this

key.

I've used the SPIF_SENDWININI CHANGE parameter with no luck. The following call is about as basic as I can get for troubleshooting this problem. Any ideas?

VB.net 1.1, Win2KPro (and XPPro) Also tried C++6.0 and VB6.0.
VB.net call

Private Declare Function SystemParameter sInfo Lib "user32" _
Alias "SystemParamete rsInfoA" (ByVal uAction As Long, ByVal _
uParam As Long, ByVal lpvParam As Long, ByVal fuWinIni As _
Long) As Long

Private Function SetScreenSaver( ByVal Active As Boolean) As Long
Dim lActiveFlag As Long = 0
If Active = True Then lActiveFlag = 1
Return = SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, lActiveFlag,

0, 0)

End Function
-Mike

[Mike S.]

I have a feeling it may have to do with the application of the screen saver
GPO. Whatever is telling user32.dll to look at the policy location in the
registry may also be saying - do not modify. Obviously if a policy was
applied, you wouldn't want a local application to overwrite it. Conversely, I
can edit the registry directly without a problem but the OS doesn't get
notified until a logoff/logon or reboot (and then the policy is reapplied).

I've gone the other route and modified the registry directly and used
SendMessage to notify the OS about the change. Unfortunately it reads just
about every configuration entry in the registry except the screen saver one.

I've tested on several PC's (5), off domain, on domain, off policy, separate
location, etc. All of them incur the same issue. No known viruses, trojans or
corrupt registries on any of them.

Thanks for your help!

"Imran Koradia" wrote:

Ok..I'm officially stumped :-S

One reason for BUFOVRFLOW is that the key does not exist in the registry. On
my machine, I have the ScreenSaveActiv e key under HKCU\Control Panel\Desktop
which is different from whats showing in your registry trace. I'm not sure
if this has got anything to do with that. Its working fine on my machine -
the value changes from 1 to 0 and vice versa correctly.
Any viruses, trojans, etc? Corrupt registry, etc?

Can't think of anything else..sorry.

Imran.

"Mike S." <Mi***@discussi ons.microsoft.c om> wrote in message
news:09******** *************** ***********@mic rosoft.com...

Still no luck. The call looks like it's going through to user32.dll, but

it's

not executing completely or properly. I am getting a return value of 0.

When I look at the registry trace I'm seeing a successful "OpenKey"

request

to HKCU\Software\P olicies\Microso ft\Windows\Cont rol Panel\Desktop. The

next

entry "QueryKey" HKCU\Software\P olicies\Microso ft\Windows\Cont rol
Panel\Desktop\S creenSaveActive fails with a result of BUFOVRFLOW. The

third

and final trace entry of "CloseKey"
HKCU\Software\P olicies\Microso ft\Windows\Cont rol Panel\Desktop completes
successfully.

"Imran Koradia" wrote:

Try using this instead:

Private Const SPI_SETSCREENSA VEACTIVE As Integer = 17
Private Const SPIF_SENDWININI CHANGE As Integer = &H2
Private Const SPIF_UPDATEINIF ILE As Integer = &H1

Return SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, iActiveFlag, _
0, SPIF_SENDWININI CHANGE Or SPIF_UPDATEINIF ILE)
hope that helps..
Imran.

"Mike S." <Mike S.@discussions. microsoft.com> wrote in message
news:41******** *************** ***********@mic rosoft.com...
> I'm using a SystemParameter sInfo call to attempt to manage the screen
saver.
> All I want to do is modify the ScreenSaveActiv e bit in the registry and have
> the OS recognize it (and occasionally set it back to -0-). Theoretically this
> should be easy to accomplish through the call shown below. If I trace the > call with SysInternals (si)Registry Monitor I can see the call being made. > Unfortunately in the si QueryValue for the key
> HKCU\Software\P olicies\Microso ft\Windows\Cont rol
> Panel\Desktop\S creenSaveActive I'm getting a result of BUFOVRFLOW (which I > assume is the trace tool unable to read the value). The value in the
registry
> does not change.
>
> We do have a forced screen saver GPO applied which I suspect may be
causing
> the failure. I have checked registry permissions and all is ok on this
key.
> I've used the SPIF_SENDWININI CHANGE parameter with no luck. The following > call is about as basic as I can get for troubleshooting this problem. Any > ideas?
>
> VB.net 1.1, Win2KPro (and XPPro) Also tried C++6.0 and VB6.0.
>
>
> VB.net call
>
> Private Declare Function SystemParameter sInfo Lib "user32" _
> Alias "SystemParamete rsInfoA" (ByVal uAction As Long, ByVal _
> uParam As Long, ByVal lpvParam As Long, ByVal fuWinIni As _
> Long) As Long
>
> Private Function SetScreenSaver( ByVal Active As Boolean) As Long
> Dim lActiveFlag As Long = 0
> If Active = True Then lActiveFlag = 1
> Return = SystemParameter sInfo(SPI_SETSC REENSAVEACTIVE, lActiveFlag, 0, 0)
> End Function
>
>
> -Mike