OLEXP: Mailto Link Does Not Work with % Character and 2 Letters (230768)



The information in this article applies to:

  • Microsoft Outlook Express 5.0 for Windows NT 4.0
  • Microsoft Outlook Express 4.01 for Windows NT 4.0 SP 1
  • Microsoft Outlook Express 4.01 for Windows NT 4.0 SP 2
  • Microsoft Outlook Express 4.0 for Windows NT 4.0
  • Microsoft Outlook Express 5.0 for Windows 98
  • Microsoft Outlook Express 4.01 for Windows 98 SP 1
  • Microsoft Outlook Express 4.01 for Windows 98 SP 2
  • Microsoft Outlook Express 5.0 for Windows 95
  • Microsoft Outlook Express 4.01 for Windows 95 SP 1
  • Microsoft Outlook Express 4.01 for Windows 95 SP 2
  • Microsoft Outlook Express 4.0 for Windows 95

This article was previously published under Q230768
For information about the differences between Microsoft Outlook Express and Microsoft Outlook e-mail clients, click the following article number to view the article in the Microsoft Knowledge Base:

257824 OL2000: Differences Between Outlook and Outlook Express

SYMPTOMS

Whenever an Outlook Express "mailto" link contains a percent character followed by 2 letter characters in the A-F or a-f range, for example %BB, the address information is not parsed correctly, damaging the address. Note that this occurs even though addresses of this type are considered to be Request For Comment (RFC) compliant.

CAUSE

This problem occurs because Outlook Express translates the percent character as an escape character. If the two characters following this percent sign are in the A-F range, they are converted to their corresponding hexadecimal values (A = 1010, B = 1011, etc) and then put together to form a single-byte value with the first character taking the upper four bits and the second taking the lower four bits. For example, %CA results in a value of 11001010.

WORKAROUND

To work around this problem, do not use a percent character followed by 2 letter characters in the A-F range in a mailto link.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.


Modification Type:MajorLast Reviewed:6/24/2004
Keywords:kbprb kbui KB230768