I have been running a function in Mathematica 10 with the command, DeleteDuplicatesBy. The function was working great until one day I started to get an error with the DeleteDuplicatesBy command. When I tried to run it, the command would turn red and say, "A symbol occurs in more than one context: One of the definitions is shadowed."

I have Mathematica 9 and 10 installed on my computer. I am not sure if that could be causing the error. Here is an image of the error in action.


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    $\begingroup$ Does this persist on restarting the kernel? $\endgroup$ – Patrick Stevens Aug 17 '15 at 18:11
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    $\begingroup$ Which contexts does the symbol appear in? (Determine this with Names["*`DeleteDuplicatesBy"].) $\endgroup$ – Patrick Stevens Aug 17 '15 at 18:25
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    $\begingroup$ Please try evaluating RebuildPacletData[] and see if this fixed the issue. $\endgroup$ – Stefan R Aug 17 '15 at 21:47
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    $\begingroup$ What version of Mathematica are you using ({$VersionNumber, $ReleaseNumber})? Try turning off the suggestions bar in Preferences, restart Mathematica, and try again. I'm wondering if it is related to this $\endgroup$ – Szabolcs Aug 18 '15 at 6:00
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    $\begingroup$ @Szabolcs I am running Mathematica 10.1, 0 I also turned off the suggestions bar in Preferences and it seems to have fixed my problem. Thank you. $\endgroup$ – hmm1050 Aug 18 '15 at 13:30

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