Pulp and Paper Canada

Opening Mystery Files

March 1, 2002  By Pulp & Paper Canada

Most readers are presumably used to attaching files to e-mails, and to receiving them. Usually, it is only necessary to double-click on the name of file in a received e-mail or in Windows Explorer, to…

Most readers are presumably used to attaching files to e-mails, and to receiving them. Usually, it is only necessary to double-click on the name of file in a received e-mail or in Windows Explorer, to open it, but most of us have been stumped by the occasional problem file and have had to resort to FedEx or other hard copy courier or else to the relatively poor quality of a fax. We will try to help you solve some of these difficulties this month.

The most probable reasons for your being unable to open a file received by e-mail or on a disc are:


You lack compatible software (Word will not open an AutoCAD drawing, for example)

Your software is an older version than the software used to generate the file.

File extension does not match your installed software

File is compressed (“zipped”) and your computer does not handle this automatically for you.

You lack Adobe’s PDF reader or the PDF extension is not appropriately registered in your computer.



The best way to read any file is by using the same software as the file’s creator did. In these days of Microsoft domination of the market for most mainstream types of software, this often takes care of itself except for the version issues discussed below.

Many software packages can read files generated by direct competitors but these file conversion routines often break down when the original file is complex. Word and Word Perfect can read each other’s files if they consist of straightforward text, but when automated tables of contents exist, or the originator uses page footers or inserts graphics, the results vary from acceptable to terrible. There is no simple way around this. In most cases, it is possible to send a simplified word processor file with the graphics in separate files. For spreadsheets, files copied as “values only” will more often convert well, but then the benefit of transferring the underlying equations is lost. You can always experiment with the originator performing the conversion to the recipient’s desired format.

Converting the original file to PDF format is usually a reliable way of transmitting files that anyone can read, but the recipient loses the benefit of being able to edit the file.

To read AutoCAD drawings if you do not have a current version of AutoCAD, one solution is to download (free) a copy of Volo View Express 2 from Autodesk’s site at http://usa.autodesk.com/adsk/index/0,,837403-123112,00.html

Quick View Plus, available for about $60US from www.avantstar.com will read most files you are likely to receive, and also some very old formats. To obtain it you have to request an Evaluation copy from the website. Site licenses for large networks are available at a lower cost per copy. Full details of the programs capability are available on the website. Notice that Quick View is often a version or so behind recent releases for the less widely-used software.


In many cases, software is confused when presented with a file created by a more recent version of the same program. The best solution is for the sender to save the file in an appropriate version (usually with the “File/Save as…..” command). This creates the problem that some features of the original file may be lost, so most originators should also save a copy in their own version. In some cases, such as Microsoft Excel, a file can be saved in a combination version, so that the best features of Excel XP are retained, but users of Excel back to version 95 can still open the file and work with it. The penalty here is that the file may be (perhaps much) larger.


When you double-click on a received file to open it, Windows uses the file extension (the three characters after the last dot in the filename) to decide which software to use to open the file. If the sender uses an unconventional extension, you may have to change it to a suitable one, using Windows Explorer (refer to help, under “rename” for instructions).

This problem is particularly common when the originating computer is a MAC, since the MAC does not need file extensions to identify files.

If you do not know the type of file you have received, you may have to do some guessing on the appropriate extension.

If someone sends a file with the wrong extension, your computer can be confused. For example, if a Word file arrives with the extension “.dwg” and you have AutoCAD installed, it will try to open the file and fail. The solution is to change the extension to the correct one. If you do not know the correct one, try “xxx”. When you double click, Windows will give you a list of programs to choose from, so you can try your luck.


Some e-mail software, including current versions of Outlook, refuses to accept files with “.EXE” extensions, since these are executable programs and may contain viruses. The solution is to ask the sender to retransmit them with a harmless extension like “zzz” and for you to rename them back to “.exe”.


Some senders compress files, most often with WinZip. These are usually known as “zipped” files. This can reduce the size of some files, such as sparsely populated Excel spreadsheets, dramatically.

When a user of AOL attaches more than one file to an e-mail, AOL zips them automatically, without telling anyone. If the recipient uses AOL, then unzipping is taken care of automatically.

Otherwise, you need to have WinZip software installed to read the files. This is available from www.WinZip.com. They offer a free trial for a month, which will get you out of trouble if stuck. I pay the $29US for a fully-licensed version, because I find it very useful.


Many people convert files to “PDF” format (Adobe’s extension for their standardized “Page Description Format”). To read them, you must have Adobe Reader installed on your computer, as discussed in the April 2000 issue of Pulp & Paper Canada. It is available as a free download from www.adobe.com. If you have a version of Adobe Reader older than version 4, you may experience strange results with recently-created PDF files. Download an update to solve the problem.


Although it is rare, a received file may be corrupted in transmission. There is no easy way of detecting this, and the only solution is to ask the originator to retransmit. Receiving a small file when you expect a large file is one indication of corruption.

xxx 103:3 (2002)Pulp & Paper Canada

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