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I am trying to write my thesis presentation with Beamer on Lyx , but i have an issue which is driving me crazy..

When i add a section/part or something else i get this error :

The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.

I also attache a screenshot in order to understand my issue :

enter image description here

Any ideas please ?

share|improve this question
I think this is improved in LyX 2.1 (to be released "soon"). – scottkosty Jun 23 '13 at 5:02
If you are using Ubuntu and want to test it out (it is quite stable now and can be installed alongside your current version of LyX), use the LyX PPA – scottkosty Jun 23 '13 at 5:03
up vote 4 down vote accepted

LyX is being a bit silly, I think.

It seems that the custom macros LyX use, \lyxframe and \lyxframeend, are only defined if you manually add BeginFrame and EndFrame to your document, from the drop down-menu in the top left. The problem occurs because LyX automatically adds an \lyxendframe first, when you add a section, but without adding the definition of \lyxendframe. Hence, you have to, at some point, add an EndFrame to your document to avoid this error.

share|improve this answer
thanks a lot !! That did work :) I have also an other issue on how to put section/title on each frame , because when i select from drop down menu section .. it does not appear :( – ALdaperan Jun 22 '13 at 18:20
@ALdaperan That is quite normal, the default beamer theme doesn't add section/subsection names, only frametitles. You should ask a separate question about that though, it is a completely different problem. (I don't know the answer anyway.) Also, please consider accepting my answer, to mark the question as answered. – Torbjørn T. Jun 22 '13 at 18:27
ook thanks a lot anyway – ALdaperan Jun 22 '13 at 18:29

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