Hier gibt’s die Lösung im Adobe-Forum:

http://forums.adobe.com/thread/853436?start=15&tstart=0

Zusammengefasst:
Open a commandbox (cmd.exe) with administrator rights.
Go to the folder C:\Program Files\Common Files\Adobe\Acrobat\ActiveX
Type regsvr32.exe /u pdfshell.dll (this command will unregister the pdfshell.dll)

Und auf Deutsch:
C:\Programme\Gemeinsame Dateien\Adobe\Acrobat\ActiveX
regsvr32.exe /u pdfshell.dll

Hier gibt’s die L\u00f6sung im Adobe-Forum:<\/p>\n

http:\/\/forums.adobe.com\/thread\/853436?start=15&tstart=0<\/a><\/p>\n

Zusammengefasst:
\nOpen a commandbox (cmd.exe) with administrator rights.
\nGo to the folder C:\\Program Files\\Common Files\\Adobe\\Acrobat\\ActiveX
\nType regsvr32.exe \/u pdfshell.dll (this command will unregister the pdfshell.dll)<\/p>\n

Und auf Deutsch:
\nC:\\Programme\\Gemeinsame Dateien\\Adobe\\Acrobat\\ActiveX
\nregsvr32.exe \/u pdfshell.dll<\/p>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[14,16],"tags":[208,301,111,13],"class_list":["post-6495","post","type-post","status-publish","format-standard","hentry","category-it","category-windows-it","tag-adobe","tag-adobe-reader","tag-outlook","tag-windows"],"_links":{"self":[{"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/posts\/6495","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/comments?post=6495"}],"version-history":[{"count":4,"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/posts\/6495\/revisions"}],"predecessor-version":[{"id":6769,"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/posts\/6495\/revisions\/6769"}],"wp:attachment":[{"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/media?parent=6495"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/categories?post=6495"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.denniskoerner.de\/blog\/wp-json\/wp\/v2\/tags?post=6495"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}