# "Duplicates not allowed" error on Asyncronous Actions
**URL:** https://www.finalbuilder.com/forums/t/duplicates-not-allowed-error-on-asyncronous-actions/3418
**Category:** Bugs
**Created:** [January 13, 2012, 10:02am UTC](https://www.finalbuilder.com/forums/t/duplicates-not-allowed-error-on-asyncronous-actions/3418 "2012-01-13T10:02:12Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@gonyoda](https://www.finalbuilder.com/forums/u/gonyoda)
#### Post date: [January 13, 2012, 10:02am UTC](https://www.finalbuilder.com/forums/t/duplicates-not-allowed-error-on-asyncronous-actions/3418/1 "2012-01-13T10:02:12Z")
This error shows up randomly on a "Run Action List" inside of an "Async Action Group". I tried making a simple project that demonstrates the failure, but I couldn't get it to fail. I can reduce/eliminate the failure by changing the Async Action Group to have a thread start delay.
```
Execute Condition (JavaScript)Condition : !DrainWebServers || ServiceMachineCount > 2Error In Execute Condition (JavaScript) Process AppTierStack #2 : Duplicates not allowed
```
```
Thanks for any help you can provide!-John Gonyo snagajob.com
```
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### Author:  [@Vincent](https://www.finalbuilder.com/forums/u/Vincent)
#### Post date: [January 14, 2012, 3:03am UTC](https://www.finalbuilder.com/forums/t/duplicates-not-allowed-error-on-asyncronous-actions/3418/2 "2012-01-14T03:03:58Z")
Hi John
I grepped our entire source tree for “Duplicates not allowed” and found 1 hit, the Add method of a dictionary class. Unfortunately this class is used everywhere! Can you run FinalBuilder with the -LOGEXCEPTIONS command line option. This will log all exceptions (handled and unhandled) to a file in your %TEMP% folder - FinalBuilderExceptions.txt. When you see the error again, close finalbuilder and send the file to “support @ finalbuilder dot com” - Note that this option will slow down FinalBuilder a lot so once you have the error occur you can stop using this option. In the mean time I’ll see if I can reproduce the problem. Sending in your FB Project file might also help us reproduce the problem too.
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### Author:  [@gonyoda](https://www.finalbuilder.com/forums/u/gonyoda)
#### Post date: [January 14, 2012, 9:26am UTC](https://www.finalbuilder.com/forums/t/duplicates-not-allowed-error-on-asyncronous-actions/3418/3 "2012-01-14T09:26:48Z")
BTW, we didn't see this until upgrading to version 1682 (from the very old 993!). We tried the 1724 and that didn't fix it. Looking at the release notes for 1682 I saw:
"Bug - Action Conditions - Fixed issue with log status of skipped actions."
Since this error seems to happen only with actions that should be skipped, maybe something was introduced during that change?
I was able to use this sample project to get the error, but it's only happened once and I didn't have log exceptions turned on. Maybe you can find it quicker than I can.
I'll let you know if I can get the sample project to reproduce the error, and I have the trace.
-J
[AsyncActionDuplicatesNotAllowedFailure.fbp7](https://www.finalbuilder.com/forums/uploads/default/original/2X/0/0b9d7a8d5672481d773317bfc2a613f17c474f91.fbp7) (55.313 KB)
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### Author:  [@gonyoda](https://www.finalbuilder.com/forums/u/gonyoda)
#### Post date: [January 14, 2012, 9:29am UTC](https://www.finalbuilder.com/forums/t/duplicates-not-allowed-error-on-asyncronous-actions/3418/4 "2012-01-14T09:29:13Z")
Wow, how about that - first try! See attached for the exception log.
[FinalBuilderExceptionLog.txt](https://www.finalbuilder.com/forums/uploads/default/original/2X/4/44f1613d360f6132538e1e8121d19c42bb826158.txt) (45.639 KB)
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### Author:  [@Vincent](https://www.finalbuilder.com/forums/u/Vincent)
#### Post date: [January 15, 2012, 3:56am UTC](https://www.finalbuilder.com/forums/t/duplicates-not-allowed-error-on-asyncronous-actions/3418/5 "2012-01-15T03:56:33Z")
Hi John
Thanks for the info. I believe I have found the problem, however I wasn’t able to reproduce the problem here at all so it’s hard to say if it is 100% resolved. This build includes some changes to hopefully solve this problem :
[https://www.finalbuilder.com/downloads/finalbuilder/aex6/FB700\_1738.exe](https://www.finalbuilder.com/downloads/finalbuilder/aex6/FB700_1738.exe)
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### Author:  [@gonyoda](https://www.finalbuilder.com/forums/u/gonyoda)
#### Post date: [February 13, 2012, 2:51am UTC](https://www.finalbuilder.com/forums/t/duplicates-not-allowed-error-on-asyncronous-actions/3418/6 "2012-02-13T02:51:43Z")
FYI: This issue was apparently resolved for us with the fix you provided. We also changed our asynchronous tasks to start up with a delay to avoid this problem in the future - and it seems to help performance somewhat.
Thanks again!
John