I previously had OpenOffice but found compatibility issues between that and MS Office. Does LibreOffice allow opening docs/xl, etc, to be opened in MS Office and vice versa?
I want to be sure that MS Office docs, etc, can be opened in LibreOffice and that LibreOffice docs, etc, can be opened in MS Office.
My experience is that using files on both MS Office and LibreOffice is at least as compatible between using MS Office files on different versions of MS Office! For simple documents, spreadsheets, and presentations, the compatibility is quite high with MSO and LibO, in fact. The more complex the file, then the higher chance of getting some glitches. This is inevitable.
Here are my main “personal rules” when I’m using files shared between LibO and MSO:
Writer:
Calc: I don’t use this much (other AskLibO users may want to offer some thoughts), but in my limited experience, Excel and Calc share my fairly simple spreadsheets just fine.
Impress: If I want to use an Impress presentation with Powerpoint (or vice versa), I always use PPT format rather than PPTX, and keep the transitions/animations very simple. Long ago, you could get some surprises in how backgrounds are handled, but this is less frequent now.
On the whole, as long as you keep your expectations in check, and avoid over-complication of documents, then sharing files between the two Office suites is fairly successful, and very convenient. YMMV.
Why do you think glitches are inevitable?
formats change, eg Microsoft modifies or introduces or updates a file format with their next version, or the other way around. Microsoft has historically had some bad practices in not adhering to file standards and add/remove certains bits of information which other applications cannot see.
Pessimistic thought suggests that Microsoft did this (or does this) because they were either carless/incompetent or nefarious. Nefarious by saving files in slightly non-standard format even though it is supposed to adhere to a standard, so they do not lose customers to other projects by having other suites not open these standard files correctly).
If you use the latest version of MS Office, then MS Office is able to use ODF1.2. LibreOffice uses a lot of extensions, in case you save to “ODF 1.2 extended”. MS Office does not know these extensions. So in case you have to switch between MS Office and LibreOffice and use ODF formats in both applications, then always save to “ODF 1.2” in LibreOffice.
Many of these extension are implemented to get a better interoperability with MS Office. Therefore you might get better results working in docx, xslx and pptx. But that depends on what the documents actually contain.
In switching between MS Office and LibreOffice you have to keep in mind, that there are principle differences between the file formats, that prevent a direct converting and need workarounds: E.g. Word has tables, which can float, so that text can be on the side of the table. That is not possible in LibreOffice. Therefore on import the table is put into a frame. But a frame cannot split about several pages. Or another example: LibreOffice Writer has the ability to vary the vertical position of an image anchored as character, that is not possible in Word. There are a lot of such subtle differences, that you always need to examine the converting result to be sure, that it meets your demands.
In case some special feature does not convert as expected, you should ask.
Compatibility issues are a never ending story which will not be solved in any foreseeable future.
That said, LO can open M$ Office files .yyy(x) and M$ Office can open at least .odt (Writer) file. I can’t tell for .ods (Calc) because I have no Office suite here.
However, don’t expect 100% compatibility because underlying concepts are different. In Calc/Excel, you may stumble on functions with different names or differing argument semantics. Last, if your files include macros, expect failure rather than success in the average case.
Collaborative work between both suites works best for basic files which don’t try to exercise bleeding edge features of the application(s). Also, always store the file native on the platform (i.e. .odx with LO, MS format with Office). Eventually export in the addressee format when sending the file but there will be approximations in the translation process. In this case, attach a version of the file in original format or PDF as a reference.
And it’s always best to backup your work to a new folder or the like before proceeding into deeper waters.
David, I use your good answer as a template for mine, OK?
For simple documents, the compatibility is quite high with MSO and LibO. Under ‘simple’, I mean first of all documents containing no embedded objects (for example, an Excel table embedded into a PowerPoint presentation makes it rather complex and problems are inevitable).
My experience:
Writer:
Calc: simple spreadsheets are just fine, but for large and complex files I would recommend Apache OpenOffice (it performs even more stable than Excel). That’s for very tables. As for charts, I have never seen an Excel file containing them that would look fine in Calc and had to re-create them (same for Writer, inter alia).
Impress: the worst degree of compatibility: if a presentation is, well, fancy (lots of objects, color transitions etc.), severe distortions are always present in my experience.
Math: Math formulas in a Writer document will appear distorted if exported to Word, however, opening them and closing (even without any editing) makes them look fine. Don’t know why.
And general advise: never do ongoing work in foreign file formats, use only ODF in LibreOffice. Only after you have finished it, export to something else.
Yep, some good advice here. Glad you found the “template” useful! 
An addition to the Word/Writer compatibility issue - Image watermark does not work at all. Watermark with an image created in Word is not recognized as watermark nor background in Writer (as of 6.2.2.2). I’ve spend hours to go back and forth trying everything I could think of. While Word can insert an image via Page Layout->Watermark->Custom, Writer only supports Text watermarks. It will treat the Word watermark as an Image object, I think, that cannot be faded nor set the transparency to not interfere with the text. What a bummer! Hope the LibO team has time to get this fixed some time.
Anyway, thanks to all you developers putting LibO together. Much appreciated. Thumbs up!
Many thanks for your answers and advice on username.
My docs and spreadsheets are not complex or macro driven so my question has been suitably answered.
Please click on the check marks at the left of each answer that helped you, so that others will know.