# Canon N670U Scanner was working, now its not, please help **URL:** \ **Category:** Printers, Scanners and Digital Cameras\ **Created:** [September 26, 2011, 2:56pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363 "2011-09-26T14:56:21Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [September 26, 2011, 2:56pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/1 "2011-09-26T14:56:21Z")
Hi There I brought this scanner (CanoScan N670U) a few months ago and it was working perfectly up until about 3 or 4 weeks ago. My operating system is Windows XP. I have been using the CanoScan Toolbox, and suddenly this stopped working, saying: “Unable to open TWAIN source Please check connection Then re-start Toolbox” I have tried a couple of other programs, but they don’t work either, I have tried unstalling the scanner and software and that didn’t work. I have downloaded a new TWAIN.dll file from the net and replaced the one in the WINDOWS folder, and that didn’t do anything. Also I can see this Scanner in my device manager saying thats fine and properly installed, and another thing, when I plug it in, it makes a little noise to show that its been turned on and has started up. Does anyone have any other suggestions?? Thanks Jackie ---
**Author:** ![Ghostman\_1](https://www.hardwareforums.com/user_avatar/www.hardwareforums.com/ghostman_1/32/183_2.png) [@Ghostman\_1](https://www.hardwareforums.com/u/Ghostman_1)\ **Post date:** [September 27, 2011, 2:34pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/2 "2011-09-27T14:34:58Z")
Uninstall the software and do a reinstall to see if that works… The software probably got corrupted !! ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [September 27, 2011, 6:42pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/3 "2011-09-27T18:42:47Z")
Thank you for your reply, but I have done that more than once and it didn’t work ---
**Author:** ![Wildcard](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/w/d26b3c/32.png) [@Wildcard](https://www.hardwareforums.com/u/Wildcard)\ **Post date:** [September 27, 2011, 7:10pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/4 "2011-09-27T19:10:52Z")
Hi, I did a search and found someone else who had the same error with a canon scanner. They had found that they needed to add an entry in the path environmental variable inside of windows. Here is the link to the fix that worked for him and several other people : [http://weblogs.asp.net/jeffwids/archive/2009/11/02/canon-scanner-unable-to-open-twain-source.aspx](http://weblogs.asp.net/jeffwids/archive/2009/11/02/canon-scanner-unable-to-open-twain-source.aspx) One thing he doesn’t mention though when editing the system variable, be sure to put a semi colon ; between the last existing entry and when you add your path to the end of it. hopefully it will work for your problem as well 🙂 ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 1, 2011, 4:42pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/5 "2011-10-01T16:42:56Z")
Hi Wildcard thank you for your reply, but it didn’t solve my problem ☹ I really don’t know how to solve this, and I dont know if I buy a new scanner that that will work Many thanks for your effort though 🙂 ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 3, 2011, 7:20pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/6 "2011-10-03T19:20:44Z")
I have unstalled the software and the actual scanner a few times now and re-installed, and added the path where the twain.dll files are to my enviroment variables, but I still get the same error “Unable to open TWAIN source Please check connection Then re-start Toolbox” I have even tried a different version of the CanoScan Toolbox. Anyone have any more ideas? Should I get a new scanner? Thanks Jackie 🙂 ---
**Author:** ![Ghostman\_1](https://www.hardwareforums.com/user_avatar/www.hardwareforums.com/ghostman_1/32/183_2.png) [@Ghostman\_1](https://www.hardwareforums.com/u/Ghostman_1)\ **Post date:** [October 4, 2011, 1:44pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/7 "2011-10-04T13:44:05Z")
When you remove the software, how are you removing it ? Add/remove programs ? After you remove the software from add/remove programs, You will need to check on your C: Program folder for ANY left over stuff it did not remove,Also look under Documents And Settings/your name /application data/ Anything that says cannon…It sounds like all the cannon software is NOT being removed before reinstalling.. ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 4, 2011, 2:25pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/8 "2011-10-04T14:25:10Z")
Yes I am removing it via Add/remove programs and then going into Program Files and deleting the Canon folder (its the only thing I have of this make). I don’t even have a folder called Application Data I can’t see anything else that says Canon. Im gonna run a search see what comes up. Thanks, Jackie 🙂 ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 4, 2011, 3:16pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/9 "2011-10-04T15:16:56Z")
Ok the only thing that comes in search is: INSTALLER\_DRIVER\_CANON\_CANOSC-0268E7A6.pf in the WINDOWS\Prefetch folder ---
**Author:** ![Ghostman\_1](https://www.hardwareforums.com/user_avatar/www.hardwareforums.com/ghostman_1/32/183_2.png) [@Ghostman\_1](https://www.hardwareforums.com/u/Ghostman_1)\ **Post date:** [October 5, 2011, 1:23pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/10 "2011-10-05T13:23:16Z")
You have to show hidden files, Double click on my computer,next at the top click on tools, then folder options… next click on View, now scroll down to show hidden files and put in a dot… Now, go into My computer/C: drive /Documents and settings/your name /Application data/ look for Any cannon there.. ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 6, 2011, 2:43pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/11 "2011-10-06T14:43:56Z")
Hi Ghostman 🙂 I have searched for hidden files and found nothing in my Application Data but there is a folder called CanoScan just in my C:/ drive I removed this and when I reinstalled the drivers again, it asked for the files in C:\CanoScan so I had to put the files back so it could copy the files over to C:\WINDOWS\twain\_32, but it still doesn’t work. I have noticed not all the files are copied over, so I have manually copied them all over before but that doesn’t work either. ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 8, 2011, 2:25pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/12 "2011-10-08T14:25:56Z")
Does anyone have any ideas on this?? ---
**Author:** ![Ghostman\_1](https://www.hardwareforums.com/user_avatar/www.hardwareforums.com/ghostman_1/32/183_2.png) [@Ghostman\_1](https://www.hardwareforums.com/u/Ghostman_1)\ **Post date:** [October 8, 2011, 3:34pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/13 "2011-10-08T15:34:17Z")
Do you have the Install disk that came with the scanner ? If you remove ALL traces of the original setup, and you do a fresh install it should work… BUT it sounds like cannon has some install files that is not being removed, The Twain files should be on the install disk.. In the long run it might just be easier to just get another scanner or an all in one printer..The only other way would be to due a total reinstall of everything.. How long has it been ? You could also try a system restore,BUT you will have to know when this FIRST started… ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 8, 2011, 5:09pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/14 "2011-10-08T17:09:24Z")
Hi thanks for the reply. No it didn’t come with an install disc. Yeah I might get another scanner. I have thought about the total reinstall of everything, but my windows XP disc is a bit old, im not sure if it still works. Its been about 10 months since I did a complete re-install of everything. It looks like my options are: Buy another Scanner or Re-install everything or I was thinking of getting a cheap second hand laptop to play with, maybe I could try installing the scanner on there if I do. Thank you Ghostman 1 for all your help Jackie 🙂 ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 12, 2011, 6:51pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/15 "2011-10-12T18:51:09Z")
I brought a laptop, and the same thing happened. The first time I installed it, I did it in this order: drivers, hardware, then the canoscan toolbox, that didnt work. So I tried to remove everything and do it like this: drivers, toolbox then the hardware but it asked for the files in C:\CanoScan again which was hidden and I removed it when trying to re-install, so I had to put the files back so it could copy the files over to C:\WINDOWS\twain\_32, but it still doesn’t work. Can anyone help?? ---
**Author:** ![Ghostman\_1](https://www.hardwareforums.com/user_avatar/www.hardwareforums.com/ghostman_1/32/183_2.png) [@Ghostman\_1](https://www.hardwareforums.com/u/Ghostman_1)\ **Post date:** [October 13, 2011, 1:20pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/16 "2011-10-13T13:20:25Z")
I would buy an all in one printer, this way you can make both of your computers happy.. There is something wrong that scanner… ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 13, 2011, 6:03pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/17 "2011-10-13T18:03:41Z")
I already have a printer though 🙂 ok im gonna get another scanner, but nothing made by Canon lol Thanks for all your help Ghostman ---
**Author:** ![Ghostman\_1](https://www.hardwareforums.com/user_avatar/www.hardwareforums.com/ghostman_1/32/183_2.png) [@Ghostman\_1](https://www.hardwareforums.com/u/Ghostman_1)\ **Post date:** [October 13, 2011, 7:28pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/18 "2011-10-13T19:28:34Z")
You are More than welcome, that is why I am here… ---
**Author:** ![Jackie1188](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/j/71c47a/32.png) [@Jackie1188](https://www.hardwareforums.com/u/Jackie1188)\ **Post date:** [October 14, 2011, 2:53pm UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/19 "2011-10-14T14:53:44Z")
aww I like you 🙂 ---
**Author:** ![Hardware\_Planet\_UK](https://www.hardwareforums.com/letter_avatar_proxy/v4/letter/h/f05b48/32.png) [@Hardware\_Planet\_UK](https://www.hardwareforums.com/u/Hardware_Planet_UK)\ **Post date:** [April 16, 2012, 5:16am UTC](https://www.hardwareforums.com/t/canon-n670u-scanner-was-working-now-its-not-please-help/28363/20 "2012-04-16T05:16:20Z")
i think you should update all the latest driver then only it will be helpful .