Dear LyX community, I have just started using LyX when writing my final thesis, so apologies in advance if the answer to my question may be straightforward. I have really tried to find out whether my question has been addressed before in the mail archive, but couldn't find anything.
Here's the problem: I want to prepare a presentation using the document classes 'presentation (slides)' or 'presentation (beamer)', but everytime I click pdflatex an error message pops up telling me "Undefined control sequence. Missing number, treated as zero." Can anybody please help me out? Thanks in advance, Thorsten