XADM: Temporary File Grows Until Disk Space Is Consumed When Sending or Receiving Mail with Attached File

When you send a uuencoded e-mail message that has attachment files with certain conditions, a temporary file may grow until it consumes all of the disk space or the information store service is shut down. This issue may also occur when you download such an e-mail message from the server by using a Post Office Protocol version 3 (POP3) or Internet Message Access Protocol Version 4rev1 (IMAP4) client.

An attachment file with the following conditions can cause this issue:

• The file includes double-byte character set (DBCS) characters in the file name.
• The length of the file name exceeds 246 bytes after the file name is converted from the SJIS character set to the JIS character set.
• The file is encoded by using uuencode.
• The codepage of the message is the JIS character set.

The temporary file is created in one of the following folders (when Exchange Server is installed in drive C by default):

• If you send the attachment file, the temporary file is created in the C:\Exchsrvr\Imcdata\Out folder.
• If you download the attachment file, the temporary file (the *.stf file) is created in the C:\Exchsrvr\Mdbdata folder.

This issue can be caused by the information store service, if a file name that includes DBCS characters exceeds 246 bytes after the file name is converted from SJIS to JIS. If this file was attached to an e-mail message, the length of file name exceeds the size of destination buffer and causes an error. The conversion is retried, which results in an endless loop that emits the same file name over and over while the temporary file grows in size.

To resolve this problem, obtain the latest service pack for Exchange Server 5.5. For additional information, click the following article number to view the article in the Microsoft Knowledge Base: The following files are available for download from the Microsoft Download Center:
For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base: Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help to prevent any unauthorized changes to the file.

Microsoft has confirmed that this is a problem in Microsoft Exchange Server version 5.5 Service Pack 2 and Service Pack 3. This problem was first corrected in Exchange Server 5.5 Service Pack 4.