Look here, about half way down the page, it looks like a registry edit
I'm offsite and I won't be able to try this myself for a few days.
Hi, I had this problem recently after upgrading to Vista64 and it was solved by installing and configuring 'Foxit' as the pdf viewer.
The following information was found in the knowledge base and although it didn't work initially, a refresh of my local user registry keys soon got it working a treat.
This is a known issue. Adobe Acrobat does not work on x64 operating system. A PDF may be viewed but there is no dynamic functionality offered such as zoom in / out etc. This issue has been identified and reported to the Enterprise PDM development team as SPR468184, ''Unable to preview PDF documents dynamically in Enterprise PDM local file vault view >> Preview tab on x64 system'. Please refer to the SolidWorks Knowledge Base to find the latest status of this SPR. Please contact your reseller in order to be added to the notification list so that you are informed when the issue is resolved.The alternative here is to use the Foxit PDF reader which does support x64 systems. Foxit Reader 3.0 can be downloaded from the following website:http://www.foxitsoftware.com/pdf/rd_intro.phpOnce Foxit is installed navigate to the following key in the registry:HKEY_LOCAL_MACHINE\SOFTWARE\SolidWorks\Applications\PDMWorks Enterprise\FileFormats\.pdfThe following list of plugins can be seen:HtmlPlugin.dll@AcroPDF.PDFHtmlPlugin.dll@PDF.PdfCtrl.6HtmlPlugin.dll@FoxitReader.DocumentInsoPlugin.dllEnsure that ‘HtmlPlugin.dll@FoxitReader.Document’ is moved to the top of the above list. Finally re-boot the machine (alternatively kill and restart explorer.exe) to ensure that Foxit is the default PDF application used in the vault.
Hope that this helps, it certainly worked for me.
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