On 11/11/03 16:56, B. Eric Bradley wrote

>I'd just drag the file onto desktop, rename it without the ._ and try 
>to open it. I suspect the extra . is what's messing things up.
>
>
>>We have a customer sending us a Photoshop eps via email. When we receive the
>>file it has ._ in front of the filename and when we try to open the file it
>>tells us it is not an eps file. She resaved the file as a tiff and the same
>>thing happens. The customer says she is not adding the ._ to the filename.
>>Is this something her email program is doing? We've received ads from this
>>person before and never had a problem. I asked if she's changed ISPs lately
>>and she said no. Any thoughts?

What is she using to send the attachment? What mail program are you using 
to read the mail?

It could be that the file is being attached as, say, appledouble (one way 
of encoding attachments), but your mail program isn't realizing the file 
is an appledouble, and hence is keeping only the wrong part of the file. 
(This would explain harry's behavior, too.)

A brief explanation:

Appledouble encodes each attachment twice - once as a mime file, and once 
as a binhex file. If the receiver doesn't understand appledouble 
encoding, it could chuck the mime file, and then badly decode the binhex 
file, giving the end result of garbage. Solutions: either have your 
sender use mime (base64) encoding to send attachments, or use a mail 
client that likes appledouble.

A long explanation:

binary files need to be turned into ascii (text) files before sending 
them across the internet, because (at least in the past) IBM mainframes 
would butcher non-text files. How the file is turned into ascii is called 
/encoding/. The unix world used uuencoding (unix-to-unix encoding) 
forever, the mac world used binhex, and the windoze world used base64 
(aka MIME). Now, the thing which caused the most pain was that mac files 
traditionally had 2 parts, a data fork, and a resource fork. Unix and 
windoze use only data forks. So... both uuencoding and base64 threw away 
info which was useful to the Mac (such as the type and creator of the 
file). Binhex, on the other hand, send something that unix and windoze 
didn't understand. Apple's reaction was appledouble, which sends both a 
mime and a binhex file, so that everyone could decode according to their 
use of resource forks. Of course, others didn't always see fit to support 
appledouble, yielding the 2 file phenomenon. This would be common in, 
say, M$ products.

Bill 


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