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Scan not working, Pixma TR4720


Hi, all of a sudden my scan feature has stopped working. Printer works fine. When I try to scan - and have tried both from computer scan utility and directly from scanner - it starts working, makes a sound as if it's scanning - but then I get an onscreen error message on my computer  that says it cannot communicate with the scanner, error code 2 157 50. Which makes no sense because my computer is clearly communicating with the scanner...(a) to print, (b) to start the scan, and (c) the scanner LED screen shows that wifi is on and has the correct name of my computer. So wifi is working, printing is working, but I can't get it to scan. And yes I have tried from IJscan gear. Help?? !! 


Product Expert
Product Expert


Sometimes if the signal drops to the printer, it can interfere with scanning. Scanning requires more signal strength compared to printing so I recommend checking that first. Please click HERE for the steps to print the network settings of your TR4720.  You will want to check row 3-2-1 and make sure it is as least 75% or higher. 

If the signal strength is good, you can try removing/reinstalling the printer/scanner driver from the Canon website. If the error still appears, you can try moving all folders from the "C:\ Windows \ TWAIN_32" folder (leave "wiatwain.ds" in there), then trying to scan again. 

If this corrects the problem, then another imaging program on the computer is interfering with the printers ability to scan.

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