|
I have an data-acquisition application in which data-logging is performed constantly and data is stored in a CF Card, which acts as the primary data-storage device for the system.
The Windows CE image that i have loaded has support for automatic detection of USB mass storage devices.
The User can retrive the data from the system (CF Card) thru USB Drive.
There is no screen or console , it is an industrial Controller.
The data acquistion goes on constantly , and the application periodically polls the USB slot to see if the user has inserted any USB Drive in it.
For this, i use the standard CreateFile() function in order to detect if the user has inserted USB Pen Drive into USB slot or not. I get the handle to the device using CreateFile(), is user has inserted it. If he has, then all reqd. data from the CF Card is copied to the USB drive.
if ((hFile=CreateFile(_TEXT"DSK2:",GENERIC_WRITE,
FILE_SHARE_READ|FILE_SHARE_WRITE, NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL, NULL))!=INVALID_HANDLE_VALUE)
{Do further processing}
NOTE: Here DSK2: is the disk number of the Pen Drive
Whenever the user insertes the USB Drive, the OS detects this, and CreateFile function therefore returns successfully with the USB dive handle. Thus, USB Drive is detected.
Now, the problem is that sometimes, although the Pen Drive is inserted, it is not detected by the OS, whearas at other times it is. That is, in the Windows Explorer, where I can see the CF Card mounted as "Hard Disk" and USB Pen Drive as "Hard Disk2", sometimes, this "Hard Disk2" is not seen. It leads me to the conclusion that the USB Dive is not mounted by the Windows Device Manager. Even if i remove the Pen Drive and re-insert it, it will not be detected hence-forth , once it is not detected. I don't know how to make the OS detect it then , the only way i know is rebooting the system. (Which is definetely not the solution!!)
What can possibly be causing this irregular behavior?
At such times, I cannot obtain a handle to the device using CreateFile. Is there any alternate way to obtain access to the USB device, rather than relying on Windows OS, and the Device Manager??
I have also completely checked the hardware, to verify that there is no problem on hardware side, no loose connections etc. Another important point is that the LED on the USB Pen Drive always glows when I insert the Pen Drive, even when it is not detected by Windows CE.
Regards,
CR
|
|
|
|
|
I am not able to find data on a HDD which has been moved from another drive using Ctrl+X. I basically Cut and paste the data from one drive to another. Now I cant find those files on the new drive, is there any way I can retreive files from the old disk from when I cut the data??
Any help would be greatly appreciated.... this is kinda very important data...
-Pav.
Pavan
|
|
|
|
|
Nope. So long as you know a partial folder name or file name, you can use Search to find the files on the target drive.
|
|
|
|
|
When I try to use taskmanager to kill certain processes, it says 'access denied'.
What I really need to know is how these files are registered as 'protected'. Why can I not kill ZoneAlarm's process? or my AV Symantec Corporate?
This is really frustrating.
Also, why can I not delete files that are currently in use? I know that it can cause a lot more than just system instability. but how does windows protect files, as well as processes? Wouldn't it be possible to have a program that would act like a virus, it would just tell the hdd to overwrite those particular clusters, period. Is there a service that protects files / processes? Or is it even more subtle than that?
The thing that I don't understand is how the permissions are set for this...can't I set the 'permissions' (or whatever they are called) to allow me to kill any process?
To sum up...I was thinking that this 'magical' prog could either:
1. delete the process from memory, like a virus.
2. reset the permissions for the process, so that I can kill it myself.
Any suggstions are very much appreciated.
sanjeev sharma
software engineer
Blog
|
|
|
|
|
Hi,
Try using third party softwares ... like tuneup utilities,etc...
Regards,
Vimal
If U Get Errors U Will Learn
If U Don't Get Errors U Have Learnt
|
|
|
|
|
i tried evry thing... you can not kill a process saying "access denied" with any third party tool.
you can try..if successful ......... please let me know also.
tried almost all
|
|
|
|
|
The reason is that these processes are using hooks into very low level functions of the OS - things like virus scanners, CD copy protection, etc often do this because they need to intercept calls to hardware functions or file access functions. The OS will not allow you to kill these processes because as I understand it, the protections around functions that run at this level are much less robust, therefore there is greater danger of causing damage if a function terminates unexpectedly.
Why do you want to kill these processes - or is this just something that interests you?
|
|
|
|
|
Just because your an admin on the machine doesn't mean you have "God" rights to everything. These processes cannot be killed because they're running in a system security context, basically in Ring 0 in the kernel space. Even as an Admin, you have no rights to kill a Ring 0 process.
sharma sanjeev wrote: Wouldn't it be possible to have a program that would act like a virus, it would just tell the hdd to overwrite those particular clusters, period.
No, because those blocks will be locked by the filesystem.
sharma sanjeev wrote: Is there a service that protects files / processes?
No, it's built into the NTFS and Security subsystems. They are not services that you see in the Service Manager.
sharma sanjeev wrote: can't I set the 'permissions' (or whatever they are called) to allow me to kill any process?
No. You can't kill, or even get permissions to kill, a process that's above your own security level.
sharma sanjeev wrote: 1. delete the process from memory, like a virus.
Can't be done. Did you think the Security Manager was just there for looks?
sharma sanjeev wrote: 2. reset the permissions for the process, so that I can kill it myself.
You cannot grant yourself permissions higher than your own account. Again, security is there for a reason.
|
|
|
|
|
So very true. Your Pentium or Pentium compatible processor has different modes that it can run in. Two of the most common are Real Mode and Protected Mode. Real Mode is a 16bit mode where one application can access and manipulate virtually everything in memory. DOS and early versions of Windows ran in Real Mode. Current operating systems run in Protected Mode. Protected Mode has 4 'rings' of protection, where Real Mode has no rings. 'Ring 0' is the ring that has access to everything. As you get into higher rings you get more and more restricted. Computer users generally have ring 2 or 3 permissions or something. That ring level does not have the rights to change its ring level. Access denied. You have to hack into the OS to do that. At that stage, whatever code you're running is a part of the 'OS' now. A screw up in coding can crash your computer or possibly even fry some hardware. This whole reply is off of memory, so if anyone notices any inaccurate information, I will not be offended by a correction.
|
|
|
|
|
Hi sanjeev,
Try SysInternal's pskill. You need to be an Administrator on the Local machine. If you have Debug Rights on the machine, you can get that group.
Jeff
|
|
|
|
|
I found my Cookies Folder missing in my Administrator Directory even after I choose "Show hidden files and folders" in Folder options.
I tried creating a Cookies folder in that Directory but it is saying that the folder already exist.
How can I make it to Cookies folder.
Help me.....
Thank u
Chandu
Thank u
Chandu
|
|
|
|
|
Uncheck Hide protected operating system files and check if you can see the folder.
Wout Louwers
|
|
|
|
|
Thank u for u r reply.
Its working.
Thank u
Chandu
|
|
|
|
|
I reinstalled my WinXP a week ago, basically erasing over the old OS, but leaving the rest of the files on the drive intact. Now I've got a hard drive full of junk that's not useable--the old Program Files directory has like 40 folders of programs that are no longer registered.
The biggest problem I have though is that when I go to open up folders from the old My Documents folder, it says access is denied. I want to delete some crap out of there to free up hard drive space, but it's not letting me. Is there any way you can access these protected folders, or do I have to reformat the whole drive again and spend a day reinstalling everything all over?
Your help is appreciated.
"Go to, I’ll no more on’t; it hath made me mad." - Hamlet
|
|
|
|
|
All of this is happening because you did not erase over your old Windows files when reinstalling. You're basically permanently locked out of your My Documents directory because it doesn't recognize your OS as being the same.
Reinstall again, but this time backup your files (to a CD or Hard Drive), then format your entire hard drive before reinstalling. Once your finished, copy everything back. This is the only way you are going to get everything back to normal.
Trinity: Neo... nobody has ever done this before.
Neo: That's why it's going to work.
|
|
|
|
|
MatrixCoder wrote: This is the only way you are going to get everything back to normal.
It very much is not.
|
|
|
|
|
You're accessing the files with a different SID, even if the account name's the same. You should be able to access the security tab on the folder, select advanced, then the 'owner' tab, and take ownership of the folder structure. That should give you the rights to do whatever you need.
|
|
|
|
|
|
Hi, I need to setup and configure ISA 2004 on windows server 2003. Does anyone know any web resource or an article about setup ISA step by step and configure internet access for user?
Thank in advance!!!
|
|
|
|
|
from sometime my system is getting hanged after half or one of browsing and continously after that.
its not like the hanging due to non respondence of any program..
its just that suddenly windows gets jam, and no control works not even cntrl+Alt+Del.
this problem is coming specially after i have installed new modem in my system.
i think this might be the reason.
i have no idea what to do.
please help.
thanks
|
|
|
|
|
I had this problem once and beleive it or not
a simple disk cleanup and defrag did the trick
---Although I think i also had spyware, but symantec
no detect
"Shorter of breath,
and one day closer to death." ~Pink Floyd
|
|
|
|
|
i accidentally deleted a C# project file and i don't use source safe so is it possible to recover the deleted project as the system was not rebooted.
|
|
|
|
|
Don't cross post in multiple forums.
|
|
|
|
|
Try any third party softwares like file recovery, etc....
If U Get Errors U Will Learn
If U Don't Get Errors U Have Learnt
|
|
|
|
|
I'd recommend setting up a source control repository, such as subversion so that this is easier in the future.
regards,
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
