I have multiple devices-a phone, a laptop, and a desktop--that all have adobe digital editions so I can download library books to whichever I am at. I didn't realize, but I have multiple Adobe IDs, and even though the help site says I can get them merged by help desk ("Contact us if you have multiple Adobe IDs and passwords and want to consolidate them.") Since thatoption is offnthe table, is there any way to look at the file, the asm, whatever, that will tell me what my login was to download the book?
You can't find it in the .acsm. The .acsm is downloaded before the book is associated with an AdobeID;
its association with the ID is created when the excrypted .epub file is created/downloaded, and held at the server end.
However, you can find the AdobeID (at least in internal form) from the .epub file.
To see the AdobeID from an encrypted .epub file:
The ID was stored only in its internal form, and not by the username that belongs to the ID.
However, if you are on ADE2.0 you can use Help/Authorization Information (ctrl-shift-I, cmd-shift-I on Mac) which will show you both the external username and the internal ID.
At least you can check that way if ADE thinks you have the correct AdobeID for the book; but if you haven't it won't remind you of the username you used.
I don't know if Adobe service are able to find the userid if you can give them that internal ID.