Vala, je viens de trouver un lien où c’est expliqué.
http://windowsxp.mvps.org/noimgresize.htm :
[quote]From pictures folder, if you click E-mail this file link in the Common Tasks pane, the Send Pictures via E-mail dialog appears for most of the image file types. For those who wish to disable this resize image dialog and directly open the email client with the image attachment, you’ll need to alter the registry and change the Perceived Type for the particular image file-type to a blank string.
Note: There may be some minor side-effects of using this method, though I’ve not experienced any problems in my system. In case of image preview problems, revert the setting by changing the Perceived Type to image. Or, type REGSVR32 SHIMGVW.DLL in Start, Run dialog to regain the functionality.
- Say for JPG image file-type, open Registry Editor and navigate to:
HKEY_CLASSES_ROOT.JPG
2. Backup the key by exporting it to a REG file.
-
In the right-pane, double-click Perceived Type and assign a blank data to it.
-
Close Registry Editor.
Similarly make changes for the other image file-types (NDRolyat: .bmp, .gif, .tiff etc.) if necessary. Resize dialog does not appear and the default E-mail client opens directly with the image attachment.[/quote]
Un autre lien pour revenir à la solution d’origine (ou quand plus rien ne marche):
http://www.jsiinc.com/SUBR/tip8700/rh8739.htm
Réflexion faite, je copie/colle, en cas de mouvement des pages:
[quote]When you attempt to perform the subject action, the Send Pictures via E-Mail wizard does NOT start, and you are NOT prompted to keep the original image size, or make the image smaller.
This behavior will occur of the Sendmail.dll file is corrupted and or the PerceivedType Value Name is NOT set to image.
To resolve this problem, I have scripted FixSPvE.bat, to replace the Sendmail.dll file from %SystemRoot%\System32\DLLCache, and to set the PerceivedType Value Name to image for the .bmp, .gif, .jpeg, .jpg, .tif and .tiff extensions.
FixSPvE.bat contains:
@echo off
Copy /Y %SystemRoot%\SYSTEM32\DLLCACHE\sendmail.dll %SystemRoot%\SYSTEM32\sendmail.dll
REG ADD "HKCR\.bmp" /V PerceivedType /T REG_SZ /D "image" /F
REG ADD "HKCR\.gif" /V PerceivedType /T REG_SZ /D "image" /F
REG ADD "HKCR\.jpg" /V PerceivedType /T REG_SZ /D "image" /F
REG ADD "HKCR\.jpeg" /V PerceivedType /T REG_SZ /D "image" /F
REG ADD "HKCR\.tif" /V PerceivedType /T REG_SZ /D "image" /F
REG ADD "HKCR\.tiff" /V PerceivedType /T REG_SZ /D "image" /F
[/quote]
Bien entendu, vous modifiez la BDR à vos risques et périls, Cafzone, Caféine et tous les participants ne pourraient être tenus pour vos conneries… euh actions 
Edit: mmenfin si tu as un problème avec l’anglais n’hésite pas à le dire ici.