If you are using Microsoft Internet Explorer 4 or 5 with the Adobe (Acrobat) Reader 4 plug-in, you may not be able to open some pdf files. You will get an empty browser screen, and the message "An error has occurred while trying to use this document" in the message area at the bottom of the browser. This incompatibility should be eliminated in the future; in the meantime, Microsoft suggests that the pdf file be downloaded and opened separately in the browser

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