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I have a canon camera from before 2011. I've made my 8GB card bootable in the camera by creating 2 partitions, boot partition of 2GB FAT16 and a FAT32 one with all the rest: photos, alternate firmware etc. I was using this procedure (specifically Method 1, Using a CHDK itself to make the SD card bootable.)

Now everything is fine and dandy, as long as I either plug the camera into the PC using Mini-USB cable (any OS) - I access the 2nd partition, or insert its SD card into an SD card reader in a Linux PC (I access both partitions).

The problem is when I want to read my photos using a PC with SD card reader. I see only the first partition. Picking disk manager shows all features concerning that partition disabled, and trying to pick "properties" results in message saying the view is out of date, and needs to be be refreshed. (of course picking the "refresh" task doesn't help.)

How do I access the second (CHDK-created) partition of such an SD card without using the camera?

Partition manager

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What is that 2nd partition formatted as? FAT32? Have you tried other SD card readers? Maybe it's a (driver) problem with that card reader functioning properly in Windows. – Karan Feb 18 '13 at 19:19
I tried with two different card readers, I may try a third one if it helps any. Other cards - same brand, same capacity just normal 1-partition Fat32 are read by these just fine, and the first partition is accessible too. – SF. Feb 18 '13 at 21:10
up vote 1 down vote accepted

I had same issue. Found the answer at

A Java utility called WASP. Used it myself under Windows 8 64-bit (so no reason why it shouldn't work with Win 7 as well). Need to launch it with waspx.cmd to gain elevated (Admin) rights. All in the readme file.

I am not the author, just a happy user!

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I found putting a copy WASP on both partitions makes switching easiest. Just remember to launch by right click and picking "run as administrator", otherwise it can't perform the changes. – SF. May 13 '15 at 17:34

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