I’m glad to say I’ve nearly finished the long slog through the file conversion aspects of this digital preservation project. After dealing with about 900 files I just have another 50 or so Powerpoints and a few Visios to get through. It’s been a salutary reminder of how easily large quantities of digital material could be lost simply because the sheer volume of files makes for a very daunting task to retrieve them.
Below are a few of the things I’ve learnt as I’ve been ploughing through the files.
Email .eml files: These are mail messages which opened up fine in Windows Live Mail when I did the scoping work for this project. Unfortunately, since then I’ve had a system crash and Live Mail was not loaded into my rebuilt machine; and Microsoft removed all Live Mail support and downloads at the end of 2017. On searching for a solution on the net, I found several suggestions to change the extension to .mht to get the message to open in a browser. This works well, but unfortunately the message header (From, To, Subject, Date) is not reproduced. I ended up downloading the Mozilla Thunderbird email application, opening each email in turn in it, taking screenshots of each screenfull of message and copying them into Powerpoint, saving each one as a JPG, and then inserting the JPGs for all the emails in a particular category into a PDF document. A bit tortuous and maybe there are better ways of doing it – but at least I ended up with the PDFs I was aiming for.
Word for Mac 3.0 files: These files did open in MS Word 2007 – but only as continuous streams of text without any formatting. After some experimentation, I discovered that doing a carriage return towards the end of the file magically re-instated most of the formatting – though some spurious text was left at the end of the file. I saved these as DOCX files.
Word for Mac 4.0 & 5.0 and Word for Windows 1.0 & 2.0: These documents all opened up OK in Word 2007. However, I found that in longer documents which had been structured as reports with contents list, the paging had got slightly out of sync so that headings, paragraphs and bullets were left orphaned on different pages. I converted such files to DOCX format in order to have the option to reinstate the correct format in the future. Files without pagination problems, or which I had been able to fix without too much effort, were all converted to PDF.
PDF-A-1b: I have previously elected to store my PDF files in the PDF-A-1b format (designed to facilitate the long term storage of documents). However, on using the conformance checker in my PDF application (e-Copy PDF Pro) I discovered that they possessed several non-conformancies; and, furthermore, the first use of e-Copy PDF Pro’s ‘FIX’ facility does not resolve all of them. I decided that trying to make each new PDF I created conform to PDF-A-1b would take up too much time and would jeopardise the project as a whole. So, I included the following statement in the Preservation Maintenance Plan that will be produced at the end of the project: “PDF files created in the previous digital preservation exercise were not conformant to the PDF-A-1b standard, and the eCopy PDF Pro ‘FIX’ facility was unable to rectify all of the non-conformances. Consideration needs to be given as to whether it is necessary to undertake work to ensure that all PDF files in the collection comply fully with the PDF-A-1b standard.”
PowerPoint – for Mac 4.0. Presentation 4.0, and 97-2003: All of these failed to open with Powerpoint 2007, so I used Zamzar to convert them. Interestingly Zamzar wouldn’t convert to PPTX – only to Powerpoint 1997-2003 which I was subsequently able to open with Powerpoint 2007. So far, it has converted over 100 Powerpoints and failed with only four (two Mac 4.0 and two Presentation 4.0). The conversions have mostly been perfect with the small exception that, in some of the files, some of the slides include a spurious ‘Click to insert title’ text box. I can’t be sure that these have been inserted during the conversion process, but I think it unlikely that I would have left so many of them in place when preparing the slides. Zamzar’s overall Powerpoint conversion capability is very good – but I have experienced a couple of irritating characteristics: first, on several occassions it has sent me an email saying the conversion has been successful but then fails to provide the converted file implying that it wasn’t able to convert the file; and second, the download screen enables five or more files to be specified for conversion but if several files are included it only converts alternate files – the other files are reported to have been converted but no converted file is provided. This problem goes away if each file is specified on its own in its own download screen. The other small constraint is that the free service will only convert a maximum of 50 files in any 24 hour period – but that seems a fair limit for what is a really useful service (at the time of writing, the fee for the cheapest level of service was $9 a month).
UPDATED and ORIGINAL: I am including UPDATED in the file title of the latest version of a file, and ORIGINAL in earlier versions of the same file, because all files relating to a specific Reference No are stored in the same Windows Explorer Folder and users need to be able to pick out the correct preserved file to open. There will be only one UPDATED file – all earlier versions will have ORIGINAL in the file title. Another way of dealing with this issue of multiple file versions would be to remove all ORIGINAL versions to separate folders. However, this would make the earlier versions invisible and harder to get at, which may not be desirable. I believe this needs further thought – and the input of requirements from future users of the collection – before the best approach can be specified.
DOCX, PPTX and XSLX: When converting MS Office documents, unless I was converting to PDF, I elected to convert to the DOCX, PPTX and XLSX formats for two reasons – it is Microsoft’s future-facing format, and that – for the time being – it provides another way of distinguishing between files that have been UPDATED and those that haven’t.
Many of these experiences came as a surprise despite the amount of scoping work that was undertaken; and that is probably inevitable. To be able to nail down every aspect of each activity would take an inordinate amount of time. There will always be a trade off between time spent planning and the amount of certainty that can be built into a plan; and it will always be necessary to be pragmatic and flexible when executing a plan.