Kinda stupid encryption question
Mar 20, 2009 | 8:15 am
#1
Original Poster
Join Date: Sep 2004
Location: Deep in the heart of...DL country.
Programs: DL GM
Posts: 3,838
Kinda stupid encryption question
I'm trying to keep 2 laptops in synch: 1 runs XP Pro SP2 with MS Office 2003; the other runs XP Pro SP2 with MS Office 2007.
I have an Excel spreadsheet that is password protected that I save in .xls (Compatibility Mode). Every time I save it in Excel 2007, I get a message:
"This document is both encrypted and password protected. The Office Open XML Formats available in the 2007 release provide stronger encryption. Do you want to increase the security of this document by converting to an Office Open XML Format?"
Am I correct in assuming that if I did so, I would not be able to open or read the file in Excel 2003?
I have an Excel spreadsheet that is password protected that I save in .xls (Compatibility Mode). Every time I save it in Excel 2007, I get a message:
"This document is both encrypted and password protected. The Office Open XML Formats available in the 2007 release provide stronger encryption. Do you want to increase the security of this document by converting to an Office Open XML Format?"
Am I correct in assuming that if I did so, I would not be able to open or read the file in Excel 2003?
Mar 20, 2009 | 9:12 am
#2
A FlyerTalk Posting Legend
Join Date: Apr 2001
Location: PSM
Posts: 69,232
If you say yes to that prompt it will be converted to the .XLSX format. If you install the Office 2007 compatibility pack on your Office 2003 system the file should still be accessible and functional. Without the compatibility pack you are correct that you would not be able to open the document on the Office 2003 system.
Mar 21, 2009 | 1:07 pm
#4
Join Date: Sep 2003
Location: Rockville MD USA
Programs: UA former 1K MM
Posts: 2,184
If you say yes to that prompt it will be converted to the .XLSX format. If you install the Office 2007 compatibility pack on your Office 2003 system the file should still be accessible and functional. Without the compatibility pack you are correct that you would not be able to open the document on the Office 2003 system.
Mar 21, 2009 | 1:12 pm
#5
A FlyerTalk Posting Legend
Join Date: Apr 2001
Location: PSM
Posts: 69,232
Microsoft Office 2007 uses SHA-1 hashing with 128 bit AES encryption in order to provide a stronger level of security. Documents encrypted using this method cannot be read by users of Office 2003 unless the Microsoft Office Compatibility Pack has been installed.
...
Even with the compatibility pack installed, Microsoft Office 2003 cannot encrypt documents using SHA-1 AES encryption, the standard for Office 2007. Instead, Office 2003 must rely on the older RC4 stream encryption technique.
...
Even with the compatibility pack installed, Microsoft Office 2003 cannot encrypt documents using SHA-1 AES encryption, the standard for Office 2007. Instead, Office 2003 must rely on the older RC4 stream encryption technique.
Mar 21, 2009 | 4:54 pm
#6
Join Date: Sep 2003
Location: Rockville MD USA
Programs: UA former 1K MM
Posts: 2,184
I see that it also says:
Note that docx files that are encrypted using Office 2007 are unable to be read by Office 2003 even if the compatibility pack is installed.
In order to encrypt a document in Office 2007 so that it can be read using Office 2003 the document mus first be protected using the Prepare -> Encrypt Document procedure described above. However, the document must then be saved using the Save As -> Word 97-2003 Document option.
Note that docx files that are encrypted using Office 2007 are unable to be read by Office 2003 even if the compatibility pack is installed.
In order to encrypt a document in Office 2007 so that it can be read using Office 2003 the document mus first be protected using the Prepare -> Encrypt Document procedure described above. However, the document must then be saved using the Save As -> Word 97-2003 Document option.
Mar 21, 2009 | 5:26 pm
#7
A FlyerTalk Posting Legend
Join Date: Apr 2001
Location: PSM
Posts: 69,232
I see that it also says:
Note that docx files that are encrypted using Office 2007 are unable to be read by Office 2003 even if the compatibility pack is installed.
In order to encrypt a document in Office 2007 so that it can be read using Office 2003 the document mus first be protected using the Prepare -> Encrypt Document procedure described above. However, the document must then be saved using the Save As -> Word 97-2003 Document option.
Note that docx files that are encrypted using Office 2007 are unable to be read by Office 2003 even if the compatibility pack is installed.
In order to encrypt a document in Office 2007 so that it can be read using Office 2003 the document mus first be protected using the Prepare -> Encrypt Document procedure described above. However, the document must then be saved using the Save As -> Word 97-2003 Document option.
Since the OP wants to work the document on both systems it is a moot point anyways.
Mar 22, 2009 | 12:31 am
#8
Join Date: Aug 2008
Location: Somewhere in Florida
Posts: 2,889
One possible solution: external encryption. I've been using TrueCrypt for a few years. With its virtual encrypted drives, it's not a hassle and the encryption is quite strong, particularly the two-pass systems.
http://www.truecrypt.org
http://www.truecrypt.org