Pptx-presentation lost formatting

hello, I made a presentation with Impress 4.2 (German) yesterday under Kubuntu 14.04. I saved it in .pptx format. Now I opened it in LO 4.2 (German) under Windows 7, and all formatting is gone, it’s a total mess. For instance, there are no line breaks, all text continues beyond the borders of the slides. I tried again under Linux, same mess, so obviously the problem is not between Windows and Linux versions. Powerpoint 2013 under Windows7, same mess.
can you help me fix this?

I fully agree with @dajare. What follows are some comments about my experience and ways to avoid problems.

In respect to MS format In general I stay as long as possible in LibO native formats and save only the last saved version in an MSO format and try to abvoid the x-formats. I made the experience that a pdf-file is in most of the cases sufficient. Many people send out files in MSO or LibO or other formats when a pdf-file is sufficient. Depending on the situation you can even secure a pdf-file against copying and changees. The pdf-export function in LibO works very well. (I am using 4.2.4.2.)

In the case of presentations I am also often asked to provide a ppt or pptx copy as a fall back solution is something happens with my PC or connection of my own PC is not possible, etc. For this I always carry a USB stick with a portable LibO version on it and my presentation. All I need is PC to plug the USB stick and can run on LIbO my own presentation.

As for MSO formats on PCs using MSO 2003, 2010, 2013 there seems to be also quite some problems, at least with the presentation templates; I am asked to look into this problem. Most likely I will recommend to change the entire company PCs from MSO to LibO.

I hope it wasn’t a big presentation. Although it’s a little late for this problem, my own advice would be: avoid PPTX!!

Impress behaves well with either the ODP or PPT formats, but PPTX causes all kinds of problems. If you have a lot of text in there, and simply want to extract it and start over, you might get some help from this early Q&A. You will see some bug reports linked in that discussion, too.

Others might have different advice for you, but I did a fair bit of checking into this (on Ubuntu and Linux Mint with recent versions of LibO Impress), and the PPTX format was consistently a problem, and a problem in the same way. Stick to ODP or PPT and you ought to be fine.