# FB Pro 6.2 Freezes when single stepping in OnFailure handler
**URL:** https://www.finalbuilder.com/forums/t/fb-pro-6-2-freezes-when-single-stepping-in-onfailure-handler/3098
**Category:** Bugs
**Created:** [April 23, 2009, 10:17am UTC](https://www.finalbuilder.com/forums/t/fb-pro-6-2-freezes-when-single-stepping-in-onfailure-handler/3098 "2009-04-23T10:17:34Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@hholtmann](https://www.finalbuilder.com/forums/u/hholtmann)
#### Post date: [April 23, 2009, 10:17am UTC](https://www.finalbuilder.com/forums/t/fb-pro-6-2-freezes-when-single-stepping-in-onfailure-handler/3098/1 "2009-04-23T10:17:34Z")
Using 30 Day free trial of FB Pro 6.2.0.1393 to do some prototype testing:
Discovered a bug while Single Stepping in the IDE running a short Main script that calls a child “Run Action List [BuildProgram]”
When the called Action List fails (VS2008 Build with missing source files)
the global OnFailure action gets called and is suppose to:
1. Export the log to HTML
2. SMPT email the log to me
a) It works if I let it run inside the IDE flat out
b) It works if I run it from the command line using FBCMD.exe
c) it FAILES when single stepping during the failure in the IDE
I have to hard kill the process
I’m on 4GB Vista 32bit OS w/SP1 and w/All Microsoft Updates
Any clue?
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### Author:  [@Vincent](https://www.finalbuilder.com/forums/u/Vincent)
#### Post date: [April 24, 2009, 9:22am UTC](https://www.finalbuilder.com/forums/t/fb-pro-6-2-freezes-when-single-stepping-in-onfailure-handler/3098/2 "2009-04-24T09:22:16Z")
Hi
Thanks for the report, I was able to reproduce and fix the problem, here’s a build with the fix included :
[https://www.finalbuilder.com/downloads/finalbuilder/620/FB620\_1446.exe](https://www.finalbuilder.com/downloads/finalbuilder/620/FB620_1446.exe)