Hi everybody!
Please I need help trying to determine the last modified date of an Excel (.XLS) file.
I used to enter this command on a Mac OS X terminal window "exiftool -time:all -a -G" and it returns;
[File] File Modification Date/Time : 2015:07:29 18:42:02+02:00
[File] File Access Date/Time : 2019:10:23 01:44:17+02:00
[File] File Inode Change Date/Time : 2019:10:23 01:43:26+02:00
[FlashPix] Last Printed : 1999:02:25 11:23:04
[FlashPix] Create Date : 1998:03:25 16:42:52
[FlashPix] Modify Date : 2012:04:27 09:58:01
I'm pretty sure that the creation date can't be in any case 1998 or 1999. This file is from an accounting book of 2011 officially sealed with MD5 hash in 2012.
How can I know it the file was modified after 2012?. This "File Modification Date/Time : 2015:07:29 18:42:02+02:00" can be a real content modification time?
Thanks!
The [File] dates don't really say anything about content changes; they're just fily system dates. E.g. the modification date will change to today if you only copy the file.
If the MD5 hash hasn't changed since it (the hash) was created, you can safely assume the file hasn't changed since then. Your best bet for knowing the last change date in that case is the [FlashPix] modify date (I'm not 100% certain, but I think that's where excel stores the date of save/modification). This should be easily verified though by taking an existing excel file and modifying/saving it again and looking at the change in dates.
Hope this helps,
Hayo
Thanks Hayo!
As you say I just verified that the modification date is stored in [FlashPix].
The problem is that when I look into another file made in the same day which is part of the accounting book and has to have the same cell values, some cells are different and the modify date is only 21 seconds after,. I think it's not possible to change the cell values and generate the file again in 21 seconds, also in no case the date of creation can be 1998 or the date of printing 1999 because we are talking about the accounting of 2011.
In other way, it's posible to know which cells were modified using any software?
Thanks!
I have no idea if other software would be able to change the dates and/or follows the "official" Microsoft way. But the create date could easily be "old" e.g. when the spreadsheet was based on an old file.