I found what seems to be a bug with Excel's encryption, when running
the same version of Excel, Excel 2003, SP3, under Vista versus XP.

As you may know, you can encrypt an Excel file by clicking, under
"Save As", then "Tools", "General Options", "Save Options" where for
"Advanced" under the Password window, you can click on a dropdown
list, that includes "Weak Encryption", "office 97/2000
compatible" (which is what I was using, before I switched), "RC4",
then "RC4, MS Strong Crypto Provider".

I saved an Excel .xls spreadsheet using the last encryption option
above, when running Excel 2003, SP3, under Vista, namely "RC4, MS
Strong Crypto Provider". This was a big mistake.

Then I tried to open this same spreadsheet, with the same program,
same password, using XP. But XP gave this error message: "Excel
cannot open this file. The encryption file used is not available,
contact the author of the file. More encryption types are available
using the High Encryption Pack."

First, I could not find the 'official' Microsoft "High Encryption
Pack" (I did find some third party stuff).

A search on the web showed that for Word2003, this is a encryption bug
as acknowledged by Microsoft. The only 'workaround' is for the sender
to resend the encrypted file under a different encryption. But what
is annoying is that I am the sender, and it's the same file, same
password, just being saved and opened under two different operating
systems (Vista and XP Professional, respectively).

Compounding the problem for me is that the two machines are presently
far apart from one another, and I would like to open this encrypted
file but cannot, even though I know the password.

Another terrible bug by MSFT--anybody have a solution? Other than
adopting Linux?

I could buy one of those Excel password cracker programs, but they say
that if you set the password at the higest level (presumeably RC4 or
above) then these programs don't work very fast.

Moral of the story: don't use RC4 since this bug exists and the end
user might not be able to open the file, even if they know the
password!

RL

Perhaps review the security settings in Vista first. You may have it
configured such that you can't access the encryption file location.

raylopez99 wrote:

I found what seems to be a bug with Excel's encryption, when running
the same version of Excel, Excel 2003, SP3, under Vista versus XP.

As you may know, you can encrypt an Excel file by clicking, under
"Save As", then "Tools", "General Options", "Save Options" where for
"Advanced" under the Password window, you can click on a dropdown
list, that includes "Weak Encryption", "office 97/2000
compatible" (which is what I was using, before I switched), "RC4",
then "RC4, MS Strong Crypto Provider".

I saved an Excel .xls spreadsheet using the last encryption option
above, when running Excel 2003, SP3, under Vista, namely "RC4, MS
Strong Crypto Provider". This was a big mistake.

Then I tried to open this same spreadsheet, with the same program,
same password, using XP. But XP gave this error message: "Excel
cannot open this file. The encryption file used is not available,
contact the author of the file. More encryption types are available
using the High Encryption Pack."

First, I could not find the 'official' Microsoft "High Encryption
Pack" (I did find some third party stuff).

A search on the web showed that for Word2003, this is a encryption bug
as acknowledged by Microsoft. The only 'workaround' is for the sender
to resend the encrypted file under a different encryption. But what
is annoying is that I am the sender, and it's the same file, same
password, just being saved and opened under two different operating
systems (Vista and XP Professional, respectively).

Compounding the problem for me is that the two machines are presently
far apart from one another, and I would like to open this encrypted
file but cannot, even though I know the password.

Another terrible bug by MSFT--anybody have a solution? Other than
adopting Linux?

I could buy one of those Excel password cracker programs, but they say
that if you set the password at the higest level (presumeably RC4 or
above) then these programs don't work very fast.

Moral of the story: don't use RC4 since this bug exists and the end
user might not be able to open the file, even if they know the
password!

RL

On May 5, 6:28*am, Bob I wrote:
Perhaps review the security settings in Vista first. You may have it
configured such that you can't access the encryption file location.

I doubt it, since I made the file in Vista, but am trying to read the
file in XP, with the same version of Excel residing on both machines.

RL