Basic Troubleshooting Scanners

Scanners convert text documents, paper photographs and images, slides and negatives, and even small three-dimensional objects into digital files. Essentially electronic copy machines, most scanners come in three main types: flatbed scanners, sheetfed scanners, and multifunction/ all-in-one devices. A flatbed scanner features a horizontal glass pane, usually in letter or legal size, on which you place a document for scanning. Scanners with an ADF (automatic document feeder; a slanted tray that holds documents for scanning) are sheetfed scanners. A sheetfed scanner may or may not include the flatbed component, and depending on the scanner model, you can place one or more documents to scan in the ADF. Finally, many multifunction or all-in-one machines include scanning capabilities, together with other features such as copying, printing, and faxing.

In addition to the hardware, most scanners come with software for editing images, previewing scans, and setting scan properties. To convert documents into digital text, many scanners include OCR (optical character recognition) software. To identify your scanner’s manufacturer and model information, first check the exterior of the scanner for brand and model labeling. If you cannot locate identifying information on the scanner itself, try the Windows Device Manager. To open the Device Manager, right-click My Computer, click Properties, select the Hardware tab, and click Device Manager. Expand the Imaging Devices section to view a list of installed devices, including scanners. Typically, scanner problems are related to one or more of four general areas: a faulty cable or connection, issues with the scanner software settings or the driver, physical characteristics of the document to be scanned, or maintenance/ cleaning issues. The following troubleshooting section discusses typical scanner problems and provides multiple solutions. If none of the suggestions work, contact the scanner manufacturer for assistance in case the scanner needs repairs or replacement. Steps For Troubleshooting Typical Scanner Problems Because most scanner problems have multiple solutions, we list a series of troubleshooting actions for each problem. Try the actions in the order presented, testing after each. If the action taken does not resolve your problem, move on to the next action.

Problem: My computer can’t find the scanner or the scanner doesn’t start scanning.

Solution 1: Check the power supply and cable. Verify that the power light is on and the scanner is ready. Make sure to use the power equipment that came with the scanner. If the power supply is plugged into a power strip or surge protector, try plugging it directly into the wall.

Solution 2: Check the USB cable, if applicable. If your scanner is connected to the computer with a USB cable, use the cable that came with the scanner. If you are using a different USB cable, it should be no more than 6-feet long. Try plugging the USB cable into a different USB port on the PC. If the USB cable is plugged into a USB hub, try connecting the cable directly to the computer. If you have another compatible cable, try replacing the current cable.

Solution 3: Check the SCSI or FireWire cable, if applicable. Some high-capacity scanners use a SCSI or FireWire interface. Use the cable that came with the scanner, and double-check the connections on your computer and the scanner itself. Try disconnecting and reconnecting the cables. If you have another compatible cable, try replacing the current cable.

Solution 4: Check the shipping lock. If the scanner has a shipping lock, verify that it is in the unlocked position. The shipping lock prevents carriage damage to the scanner during shipping.

Solution 5: Reset the scanner. Follow the manufacturer’s instructions to reset the scanner. If you do not have instructions, disconnect the cable that connects the scanner to the computer. Disconnect the scanner power cable to turn the scanner off. Turn off the computer and wait a couple of minutes. Turn on the computer, reconnect the scanner power cable to turn the scanner on, and reconnect the cable that connects the scanner to the computer.

Solution 6: Update the scanner driver and software. Check for updates to device drivers and new software patches. Install the updates as instructed by the manufacturer.

Solution 7: Check the device driver in the Windows Device Manager. To open the Device Manager, right-click My Computer, click Properties, select the Hardware tab, and click Device Manager. Look in the Imaging Devices section for a yellow exclamation mark or red X indicating a problem with the device or driver. If a problem is indicated, right-click the scanner and click Properties. In the Device Status box, look for any messages about problems with the scanner, or click the Troubleshooting button for additional help.

Solution 8: Verify scanning software settings. Most scanning software automatically opens when you attempt to perform a scan. If yours does not, open the software manually. If you don’t know the correct software settings, change the settings to the factory default, or refer to the software’s online help or support information.

Solution 9: Close all open programs and disable antivirus software. If this solves the problem, the antivirus software may be interfering with the scanning software. Check with the antivirus software manufacturer to resolve the conflict.

Solution 10: Try repairing the scanner software. Click Start, Control Panel, and Add Or Remove Programs. Select the scanning software and click Change or Repair. Follow the onscreen instructions.

Solution 11: Uninstall and reinstall scanner software. Click Start, Control Panel, and Add Or Remove Programs. Select the scanning software and click Remove. Follow the on-screen instructions to remove the software. Reinstall the scanner software using the original installation CD.

Problem: I don’t have enough disk space, or memory errors occur when I use my scanner.

Solution 1: Try scanning to a lower resolution. Most scanners let you scan at different resolutions. Image resolution is measured in dpi (dots per inch), which is sometimes referred to as ppi (pixels per inch). As dpi/ppi increases, so do image quality and file sizes. How you plan to use the scanned image dictates the dpi/ppi level to use. Ideally, you can use the following guidelines for dpi/ppi settings. If your computer is running out of memory or hard drive space, however, try a lower setting. Image for email or CRT (cathode ray tube) display: 75dpi/ppi Image for on-screen LCD display: 200dpi/ppi Text documents and medium quality images for printing: 300dpi /ppi High-quality images for printing: 600dpi/ppi High-quality images for enlarging: 1,200dpi/ppi (may require 100MB or more of drive space)

Solution 2: Reduce memory use. Close all unnecessary applications, such as email and word processing software. You can also reduce the number applications running in the background with the Windows configuration tool. To do this, click Start and Run. In the Open dialogue box, type msconfig and click OK. Select the Startup tab and remove the checks from any applications you do not want your computer to start automatically. If you’re not sure, do not remove the check write down the name of the item and research it later. When you have completed unchecking items, click OK and restart your computer. Windows restarts in the Selective Startup state. If your system does not operate correctly in Selective Startup or you want to return to the previous state, select Normal Startup and restart Windows again.

Solution 3: Increase hard drive space. To up the amount of space available on your computer’s hard drive, start by emptying the Recycle Bin. To do this, right-click the Recycle Bin on the Windows Desktop and click Empty. You can also run the Disk Cleanup utility. To do this, click Start, Programs, Accessories, System Tools, and Disk Cleanup. Follow the on-screen prompts to select files to remove. You can free additional space by removing applications you do not need. Click Start, Settings, Control Panel, and Add Or Remove Programs. For each application you no longer need, select the application and click Remove.


Problem: My ADF is experiencing feed errors and paper jams.

Solution 1: Inspect documents for obstructions. Make sure the documents you are attempting to scan do not have staples, paper clips, binder holes, glued edges, punch holes, tears, or other characteristics that interfere with the ADF.

Solution 2: Check document compatibility. Do not place documents in the feeder that the ADF is not designed to handle, such as multipart forms. If you’re scanning a document that’s not a standard size, check the scanner documentation to verify the sizes it supports.

Solution 3: Confirm ADF installation and document placement. Verify the ADF is installed properly and in the correct position. If you are scanning multiple documents, do not exceed the recommended ADF capacity, and fan the pages prior to placing them in the ADF to separate them.

Solution 4: Work with different types of documents and sizes. If you are scanning pages of different sizes, try scanning only the same size pages at the same time, or scan each page one at a time. If the paper has a glossy or semi-glossy coating, try non-glossy paper.

Solution 5: Clean the ADF. Follow the manufacturer’s instructions for cleaning the ADF assembly. If parts such as pads or rollers appear worn, refer to the manufacturer’s instructions for replacing them.

Problem: My scans are blank or of poor quality.

Solution 1: Check ADF document placement. If you are using an ADF, make sure you have placed the documents correctly in the ADF. For example, make sure it is facing up or down, as indicated in the manufacturer’s directions.

Solution 2: Inspect the original document or image. Verify that the original is clear and not distorted or damaged.

Solution 3: Clean the scanner glass. Most manufacturers recommend cleaning with a lint-free cloth and nonabrasive glass cleaner or isopropyl alcohol.

Solution 4: Preview the scan. If available, use your scanning software’s preview feature to verify the scan quality. Adjust software settings to increase sharpness and/or resolution. For color images, use 24-bit output, and for black and white use 256 shades of gray (8-bit grayscale).

Solution 5: Check the scanning software. Verify that photo scanning is not selected for text or line drawings and vice versa.

Solution 6: Check for bleed through. If the original document is two-sided, the information from the reverse side of the document may bleed through. Adjust brightness, contrast, and threshold settings to reduce bleed through.

Solution 7: Reinstall or update the scanner driver. Check the manufacturer’s Web site for an updated driver or reinstall the current driver following the manufacturer’s instructions.

Problem: My scans have vertical lines or stains.

Solution 1: Scan a blank sheet of paper. If the lines or stains continue to appear, clean the scanner components.

Solution 2: Clean the scanner glass. Most manufacturers recommend cleaning with a lint-free cloth and nonabrasive glass cleaner or isopropyl alcohol.

Solution 3: Clean the ADF mechanism. Follow the manufacturer’s instructions for cleaning the ADF assembly. If parts such as pads or rollers appear worn, refer to the manufacturer’s instructions for replacing them.

Problem: The scans are clipped, incomplete, or skewed.

Solution 1: Place the image or document correctly. If you are placing the image on a scanning bed, make sure it is positioned correctly. Try turning the image 90 degrees and rescanning.

Solution 2: Check ADF issues. If you are using an ADF, align the page in the sheet guides and do not exceed the ADF sheet capacity. Make sure the sheet guides are not loose or broken. For multi-page scans, especially pages of different sizes, scan one page at a time. If the paper you’re using has a glossy or semi-glossy coating, try non-glossy paper.

Solution 3: Verify your scanner’s software settings. Check whether your scanning software has an automatic cropping feature enabled. Additionally, if the scanning software includes an automatic straightening feature, it may attempt to straighten an image that includes a large graphical design. Turn the feature off and try the scan again. If a page is missing from the scanned document, turn off any scanning software options that automatically remove blank pages.

Problem: The scanned image’s color or brightness is incorrect.

Solution 1: Verify software settings. Check the settings for color and brightness. Adjust as needed, using the preview feature if available.

Solution 2: Move the document. Try rotating the original document 90 degrees in the scanner.

Solution 3: Use default settings. Set the scanner and software to the original factory default settings.

Solution 4: Adjust settings for colored paper. If you are using colored paper, set the output type to black and white. Change the color channel to red, green, or blue to determine the channel that works best with the background. Magazine pictures and postcards might benefit from the descreening option, if available, which reduces undesirable patterns.

Problem: Scanning is very slow.

Solution 1: Change to black and white. Reduce scan time by choosing black-and-white output, if possible.

Solution 2: Adjust resolution and file size. Modify the scanner software to reduce the resolution and decrease the file size. Avoid using the 24-bit color output, if possible. Lower-quality settings generally result in faster scans.

Solution 3: Decrease the image size. Crop or resize the photo to a smaller scan dimension.

Problem: Text created by the OCR software is incorrect.

Solution 1: Ensure software settings are correct. Check the scanner software to be sure you selected a text document for scanning. Also, select a minimum dpi of 300. Even under ideal conditions, the OCR software may not be able to convert all text correctly.

Solution 2: Check the original document. OCR software is less reliable when the quality of the original document is poor.

Solution 3: Reformat the scanned document. Word processors may not be able to read all of the scanned document’s fonts if the font is not available on your PC. Also, the OCR software may not preserve columns, tables, and other formatting. Use the word processor to reformat the document as needed after scanning.