You can download this HotFix from TIBCO Support Portal (https://support.tibco.com). You will need to provide your TIBCO Support Portal credentials. Once logged in you can the download the hotfix by selecting the “Downloads” -> “Hotfixes” option. Then go to the AvailableDownloads/BusinessWorks/6.4.2/hotfix-11.

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Closed Issues in 6.4.2_HF-011 (This Release)

AMBW-36837
For XML to JSON conversion, the leading and trailing spaces were trimmed.

AMBW-36499 
Applications failed to start on AIX platform.

AMBW-36169
The JDBC Connection resource now has a Connection Idle Timeout field with second, 
minute, and hour input options. For ideal timeout, add a value greater than zero.

AMBW-36069
TIBCO Business Studio for BusinessWorks displayed an error  when a policy 
resource was in a shared module.

AMBW-35859
Under heavy load, Basic Authentication policy when applied on a REST end point 
called  a spawned job and generated  NullPointerException.

AMBW-35846
The Receive Mail activity displayed an error message for emails with attachment 
for Microsoft Outlook mail server. 

AMBW 35837 
Under heavy load, Basic Authentication policy when applied on a REST end point 
called  a spawned job and generated  ConcurrentModificationException.

AWBW-35680
Profile name changed to default name if value of any module property was edited.

AMBW 35632 
TIBCO ActiveMatrix BusinessWorks generated Null Pointer Exception  under heavy 
load when a policy was applied on an application.

AWBW-35030
The Copy Of function added unused namespaces declared inside a source activity. 
Select the copy-of target element. Open Show/Hide edit tab. 
Clear the copy-namespaces check box to not carry parent namespaces.

AWBW-33599
During migration, the .xsd files took more time than expected.
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You can also download the hotfix using the below link:

https://support.tibco.com/s/hotfixes?id=a011a00000FjyIPAAZ