windows System Image fails at about 150 gigs

i'm trying to create a system image (Win7 home ) on an external drive, but it fails after writing about 150gig of an estimated 160gigs. i have done the following...

- chkdsk /r on source and destination - both drives are fine
- using a 500gig external drive with 330gig free & a 1 TB drive with 800 gigs free - both fail at about 150gig
- defrag on destination drive - same failure
- increased external drive system protection level to 100% - same failure

i'm out of ideas... other than backing up & deleting data files before writing the image to get it well below 150gig. is there an image size limit setting or something?

thanks all

edit - actual message is "... I/O device error 8007045D

that would be my preference - it's not my pc

Did you run chkdsk /r from the recovery console ?

Andyrids said:

Did you run chkdsk /r from the recovery console ?

no - on the pc chkdsk /r was run at startup and on the external drive it was run from an admin cmd prompt

mjf said:

I would also try a different USB port. As alluded to above you could try the free Macrium Reflect. You can run this from the the Macrium Recovery pe CD.
Imaging with free Macrium
BTW a 160 GB image for the OS partition is getting too large in my opinion because of the time to image and reimage. The owner of the PC might want to move some data off the OS partition.

i'll try a different usb port - but i think i might have done this already inadvertently

that is what i'm eventually going to do - make a data partition - but i wanted to have an image first - like i said above i could try deleting the user data to make the image and then restore to the new partition, but this shouldn't be necessary - and might not help anyway - 160gig shouldn't be too big these days

well - the system image worked when i changed USB ports which i thought was crazy so i tried it again on the port it had just worked on and... it failed.

out of curiosity, why would changing USB ports make a difference?

still don't know what's going wrong with these images but i'm going to move on with the drive partition - just for others reference i'll post back if the errors disappear with the new partition minus the data files

That I/O error is telling you that there is problems reading/writing to the disk, bad clusters / blocks is the usual problem in that case (though a defective USB cable or port can also produce the same error) chkdsk /r should have taken roughly an hour to run if it was looking for and reallocating any bad blocks. Though I have known it to not find them all in the past after only one run and even then depending on the severity / quantity of bad blocks zero filling the entire drive at times has been the only solution but obviously you need the data backed up first like you are trying to do...

I would not be using windows imaging for this task... In situations like this the only imaging software I have found to work with bad drives is Drive Image XML don't let the crappy looking GUI put you off, this program will also tell you where the bad blocks are and continue reading unlike other software.