Cyclic Redundancy Check on External Hard Drive

External hard drive isn't showing up in My Computer. When I try to open up in disk management, it throws a "Cyclic Redundancy Check" error message. After doing some digging online, most solutions involve running dskchk in the command prompt, but when I do, it says that the drive is RAW and it can't be done. I can't find a solution for this. Please help!

Can you get it to show up on any other computers?
- Peter

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Check virus of external hard drive (in a safe way) and TPM security chip request

Hello.
Context, complain:
I had few trouble with my new lenovo R61. But today everything is alright, downgrade to xp ok, driver graphic card ok, partitioning ok. Westerday I was in the same point with Avast anti virus installed, comodo firewall install. I decide to install spybot and check an external hard drive. I allowed the choice of spybot to do something with some "dangerous files". After this point I was not allowed to do nothing in the computor. "your not allowed to shut down the computer". "your not allowed to...contact admin". "your not allowed"....
I forced the restart, press blue, recovered the system and decide to accept the norton help, so I have norton install.
Request1:
I want to check my external I drive with any risk for the system, what can I do, I'm I in risk as I plug in?
Request2:
Second small problem, when I try to enrolled my finger, it ask me for TPM code that I do not have. Is it safe to go in the bios and clear security chip, I see some warning in the doc.
Thanks
Tom
Solved!
Go to Solution.

Ok thanks!
I've resolve both problem yesterday evening,
My computer is now ready to operate and my hard drive looks clean now (that's what says norton and sophos anti-virus). I hope that is true. That's was quiet stressfull to have a virus attack after 1 day. Somebody suggest me that's maybe I don't restart before using Spybot creating a big mess in the registry.... I'll never now.
But now ALL GOOD YEAH
Tom

Transferring i tunes library to external hard drive

to be honest, i am not mac savvy, so i am obviously doing something wrong. i am trying to transfer my i tunes library to my external hard drive. i have made multiple attempts, including consolidating, but it doesn't seem to work. i go thru the process and check the external hard drives and the songs are not there. any suggestions on how to take care of this issue are appreciated.

welcome to Apple discussions !
click here for tips/instructions on how to move your library properly.
JGG

IPhoto on external hard drive

I use iPhoto library manager to manage many iPhoto libraries which I keep on external hard drive. I have run into a problem, however. When loading photos into my library, I began to get a message that there was not enough disk space. I checked my external hard drive, but there was sufficient space. Then I realized that my INTERNAL hard drive was filling up as I uploaded photos. What I don't understand is WHY? My library is definitely on the external hard drive, but could iphoto be making a copy in the internal one? Help!! I am at a loss. Many thanks.

mcswiss
Sounds like there's a library lurking on your internal HD somewhere.
In the iPhoto Window select a pic and right click on it and go Show Original.
A Finder window will open with the file selected. In column view you will be able to track back to the location of the library.
If, for some reason that doesn't find it, in the Finder -> Go Menu select 'Go To Folder' and type
/Volumes
to the resulting window. See if you can find another library there.
Regards
TD

I need to move my iTunes library to an external hard drive

I need to move my iTuns library to an external hard drive in order to free up space on my macbook pro. I've checked the external hard drive & it is playing my iTunes fine. I've moved the iTunes folder on my macbook to the trash can. Is there anything else I need to do before emptying it from the trash can?

Sounds like you are OK. Be sure to open iTunes then preferences. Click on Advanced icon in toolbar. Set the path to your media folder in the field where you should see the path to the original location. Or, you can hold down the OPTION key while starting iTunes and choosing the library you wish to use.
This should be it. If all is working well delete the data in the Trash. Now, if it were me I would have a backup somewhere just in case. Better safe than sorry.

Mount an external hard drive in single user mode

Do any know how to mount an external hard drive in single user mode:
I've issue the following command:
/sbin/mount -uw /
mkdir /Volumes/ex1
/sbin/mount_hfs /dev/disk2s3 /Volumes/ex1
(I've checked my external hard drive using df -k showing the device is disk2s3)
Result:
Permission denied

Hi leung wai,
   I wouldn't mind knowing the answer myself. I think the problem with doing it in the manner you attempted is that the device tree hasn't been created yet so the mount command is certainly not going to work. I assume that the answer is to start up enough of the system to have the device tree created. Unfortunately, I don't know where in the startup process that occurs. You could try the following command after making the boot volume writable:
/usr/libexec/registermach_bootstrapservers /etc/mach_init.d
Then check to see if the /dev virtual filesystem has been created. Of course it wouldn't surprise me if that didn't also mount your disks. If not, try the following:
/sbin/SystemStarter
It should have been created after that because at that point almost the whole system has started.
Gary
~~~~
   You've been telling me to relax all the way here, and
   now you're telling me just to be myself?
         -- The Return of the Secaucus Seven

Mount external Hard drive in Single user mode

Do any know how to mount an external hard drive in single user mode:
I've issue the following command:
/sbin/mount -uw /
mkdir /Volumes/ex1
/sbin/mount_hfs /dev/disk2s3 /Volumes/ex1
(I've checked my external hard drive using df -k showing the device is disk2s3)
Result:
Permission denied

I seem to remember the "Permission denied" or "Device busy" coming up in some situations but not others when attempting to mount drives at this early stage in "single user" mode...
It might be worth trying to run:<pre>sh /etc/rc</pre>This is actually present among the "Tiger" messages in "Single User" mode, as the procedure to continue booting but remaining in "single user" mode. Indeed, it seems to start up the usual "services" like starting disk arbitration (so you can eg. use 'diskutil' to repair permissions, or loading "NetInfo" so you don't need to work in '-raw' mode - in the past, people had posted complicated procedures for doing these things manually.
After running the 'rc' script, try creating your mount point and and running 'mount_hfs' as usual...

Problems with itunes 10 and external hard drive

Hi
I was recently forced to change the internal hard drive on my G5 Tower, and the external hard drive where I keep my music library.
The new external drive had all my music files copied to it. I reloaded my itunes library files (that I had backed up from old computer) into my music folder and I named the new external drive as the media folder in Itunes preferences. The first time I used itunes it asked me if I wanted it to locate all files to which I pressed OK. itunes quickly found the majority of files and I cleaned up / organized the small mess left behind.
Trouble is a few problems have occurred. Firstly, itunes seems slow – there’s a sluggish pause flicking between tracks – where as before it used to snap into response. Occasionally I’m asked to locate files which I thought was a task it had already done - and every now and again when I check the external hard drive music library I find files have been moved from there album locations to ‘untitled’ folders, etc. I can only assume itunes is doing this. I’ve also noticed I can’t remove the external hard drive from the desktop without closing itunes first which never happened before.
This is getting somewhat frustrating. Can anybody advise?
Much appreciated.
K

Hi Nick,
Avoid the WD files completely, not needed & often a problem.
You need to erase the Drive, & to use it on both Format it MS-DOS/FAT32, on the Mac or PC, but will have a 4 GB filesize limit, as well as other limitations.
One option not mentioned yet is MacDrive for your PCs... allows them to Read/Write & Format HFS+, so no need to reformat it...
http://www.mediafour.com/products/macdrive/

I am using Windows 8.1 i have an External Hard Disk and one drive is now inaccessible due to sudden power failure few days ago. Now it shows "Data error (Cyclic redundancy check)". I want all my important files and Pics. How ?

Hi,
I am using Windows 8.1
I have an External Hard Disk i have partitioned it to 4 parts.
One drive is now inaccessible due to sudden power failure while listening Music from that drive few days ago.
Now it shows "Data error (Cyclic redundancy check)".
I tried all the procedures provided here like
chkdsk /f, diskpart, rescan etc
but no result :( (i mean all processes failed. They could not detect the drive).
Please help me to get those data, pictures and project files.
thank you

Then why aren't you posting this in the Windows 8 forums found @
http://social.technet.microsoft.com/Forums/windows/en-US/home?category=w8itpro
This is a Windows 7 forum for discussion about Windows 7.
Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. ”

I am trying to backup my Itunes onto my external hard drive. I am at the step where I on Itunes, click on File - Library - Organize library. I am suppose to check mark both boxes there, It won't allow me to check mark the second box, why? How to fix this.

I am trying to backup my Itunes onto my external hard drive. I am at the step where I on Itunes, click on File ->Library ->Organize library. I am suppose to check mark both boxes there, the first being "Consolidate Files" & the second being "Reorganize files in the folder 'Itunes Media'. I am able to checkmark the first box but It won't allow me to check mark the second box, why? How can i fix this? Please help!

Well you must have made a mistake somewhere. The last instruction of step four reads:
When you've found your iTunes library folder, drag that folder to your external hard drive. This will begin the iTunes backup. The amount of time the backup will take depends on the size of your library. When the transfer is done, your backup is complete and your external hard drive can be disconnected.
Normally dragging content from to a new location on a different drive will result in a copy action which is what you were supposed to do. At a guess you somehow managed to move the iTunes folder. Then when you started iTunes it created a new blank library for you assuming it had just been installed rather that raising a warning.
Close iTunes. Rename the iTunes folder on the internal drive as iTunes (Empty) then copy the iTunes folder from the external back into the User's Music folder. Start iTunes. All should be well.
When you've made sure it all works please read my User Tip and use that method to backup in future. Since you already have a folder with the backup in place you can skip the "Make New" operation in the fourth step and simply choose the external folder.
tt2

External Hard Drives and Check Disk

I have an external NTFS hard drive that for some reason when I go to do an Error-Check with Window's Check Disk feature it says it can't check the disk while it is in use and I then proceed to schedule a scan at start up.
This is an External USB device and it appears you can not do scheduled scans on them. I restart the computer and nothing happens, no scan.
Can we get some support for scheduled scans on external hard drives?

Did you try the CHKDSK /X option? CHKDSK /? gives you a list of options.
CHKDSK [volume[[path]filename]]] [/F] [/V] [/R] [/X] [/I] [/C] [/L[:size]] [/B]
volume          Specifies the drive letter (followed by a colon),
                  mount point, or volume name.
filename        FAT/FAT32 only: Specifies the files to check for fragmentation.
/F              Fixes errors on the disk.
/V              On FAT/FAT32: Displays the full path and name of every file
                  on the disk.
                  On NTFS: Displays cleanup messages if any.
/R              Locates bad sectors and recovers readable information
                  (implies /F).
/L:size         NTFS only: Changes the log file size to the specified number
                  of kilobytes. If size is not specified, displays current
                  size.
/X              Forces the volume to dismount first if necessary.
                  All opened handles to the volume would then be invalid
                  (implies /F).
/I              NTFS only: Performs a less vigorous check of index entries.
/C              NTFS only: Skips checking of cycles within the folder
                  structure.
/B              NTFS only: Re-evaluates bad clusters on the volume
                  (implies /R)
The /I or /C switch reduces the amount of time required to run Chkdsk by
skipping certain checks of the volume.
Thanks,
-Saravana

Hi! I have a WD my book external hard drive plugged into my imac and I want to share it over my network with my apple tv. I went into system preferences sharing, checked "file sharing" and added my external hard drive to the shared folder. So now it is

Hi!
I have a WD my book external hard drive plugged into my imac and I want to share it over my network with my apple tv. I went into system preferences > sharing, checked "file sharing" and added my external hard drive to the shared folder. So now it is listed in "shared folders" but under "users" everything is grayed out (it says "read and write" for "everyone" - but "read and write" is grayed out, and it doesn't let me add or subtract users). Now I can access all of the folders I shared from my imac except for the externalhard drive. What's going on?

Hi RRFS!,thanks for help.I forgot to tell that hard drive has 2 partitions 1:format :Mac OS Extended (Journaled) and that works properly,2:format:MS-DOS (FAT32) and when i "get info" for both :first has shering & permitions:You can read and write - with name and privilege, second has shaing & prermissions:You can read and write- without name and privilege

My toshiba external hard drive is not being recognized, except when I eject it. I have the preferences checked to show icon and have checked utilities folder. nothing. Help!

I have a iMac, Yosemite 10.10 and my toshiba external hard drive is not being recognized, except when I eject it!. I have the preferences checked to show icons and have looked in the utilities folder..nothing. I have also changed ports. ??

A few things to try:
1-Repair permissions and restart your computer.
2-Zap the PRAM
3-Use Software Update/App Store to update your OS to OS 10.10.3. Also, update everything SU/AS has to offer for your computer. When done, repair permissions and restart your computer.

Best tool to check i/o of external hard drive??

I'm using a couple different external hard drives and simply want to check the i/o on them to determine which is the fastest for data storage & retrieval. Wondering what the best tool might be for this test??
Thanks in advance for any feedback.

I found a utility called mmbench that does just that. It's a few years old, and not in active development , but works on my iMac with 10.6.3.
http://www.macupdate.com/info.php/id/17804/mbbench

How do I make my external hard drive show up in devices even when the external discs box is checked in preferences?

External hard drive not showing up in devices, even after troubleshooting and checked in preferences.

OK I solved my own problem. My iPhone was plugged into the other USB port in addition to the external hard drive. I took out the iPhone USB and switched the external hard drive USB to the other USB port. The drive showed up in my devices!

Cyclic Redundancy Check on External Hard Drive

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