Hi Andre,
Can you try this method using TFTP;
Downloading an Image File by Using TFTP
You can download a new image file and replace the current image or keep the current image.
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Caution For the download and upload algorithms to operate properly, do not rename image directories.
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Beginning in privileged EXEC mode, follow Steps 1 through 3 to download a new image from a TFTP server and overwrite the existing image.
Command Purpose
Step 1
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Copy the image to the appropriate TFTP directory on the workstation. Make sure the TFTP server is properly configured; see the "Preparing to Download or Upload an Image File by Using TFTP" section
Step 2
Log into the access point through a Telnet session.
Step 3
archive download-sw /overwrite /reload tftp:[[//location]/directory]/image-name
Download the image file from the TFTP server to the access point, and overwrite the current image.
•The /overwrite option overwrites the software image in Flash with the downloaded image.
•The /reload option reloads the system after downloading the image unless the configuration has been changed and not saved.
•For //location, specify the IP address of the TFTP server.
•For /directory/image-name, specify the directory (optional) and the image to download. Directory and image names are case sensitive.
Step 4
archive download-sw /leave-old-sw /reload tftp:[[//location]/directory]/image-name
Download the image file from the TFTP server to the access point, and keep the current image.
•The /leave-old-sw option keeps the old software version after a download.
•The /reload option reloads the system after downloading the image unless the configuration has been changed and not saved.
•For //location, specify the IP address of the TFTP server.
•For /directory/image-name, specify the directory (optional) and the image to download. Directory and image names are case sensitive.
Note To avoid an unsuccessful download, use the archive download-sw /safe command, which downloads the image first and does not delete the current running version until the download succeeds.
The download algorithm verifies that the image is appropriate for the access point model and that enough DRAM is present, or it aborts the process and reports an error. If you specify the /overwrite option, the download algorithm removes the existing image on the Flash device whether or not it is the same as the new one, downloads the new image, and then reloads the software.
Note If the Flash device has sufficient space to hold two images and you want to overwrite one of these images with the same version, you must specify the /overwrite option.
If you specify the /leave-old-sw, the existing files are not removed. If there is not enough space to install the new image and keep the current running image, the download process stops, and an error message is displayed.
The algorithm installs the downloaded image on the system board Flash device (flash:). The image is placed into a new directory named with the software version string, and the system boot path variable is updated to point to the newly installed image.
If you kept the old image during the download process (you specified the /leave-old-sw keyword), you can remove it by entering the delete /force /recursive filesystem:/file-url privileged EXEC command. For filesystem, use flash: for the system board Flash device. For file-url, enter the directory name of the old image. All the files in the directory and the directory are removed.
http://www.cisco.com/en/US/docs/wireless/access_point/12.3_2_JA/configuration/guide/s32mfw.html#wp1035507
Hope this helps!
Rob
