If you are using Reader 7 you may want to disable the option “Keep forms data temporarily on disk“.
This prevents form data being cached on the local disk, which may pose data integrity/security risks to enterprise customers.
There are a few workarounds to disble this functionality:
1. create a registry key to disable the option automatically:
The location is [HKEY_CURRENT_USER\Software\Adobe\Acrobat Reader\7.0\Originals].
Create the key named bCacheFormData.
Create a dword value of 00000000.
Close registry and relaunch Acrobat/Reader.
this.nocache = true;
This will only have an affect in the form context.
3. Your third option is to use the Web browser settings:
Set the preference “Do not save encrypted pages to disk” as checked.
Empty Temporary Internet Files Folder when browser is closed.
This setting has been disbled by default in Acrobat/Reader 8.0 and later versions.