outlook 2019出现office的word ppt excel等不能预览，提示不能预览此文件，因为没有为其安装预览程序，实际上查看outlook---选项---信任中心---信任中心设置---附件处理---附件和文档预览器，里面都有相关预览器，打开注册表（win+R后输入regedit回车），打开路径计算机\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\PreviewHandlers，确认注册表属性如下，如果不是，修改值即可，修改前最好先备份一下。
excle的如下：
"{00020827-0000-0000-C000-000000000046}"="Microsoft App-V Preview Handler for .xltx"
viso：
"{21E17C2F-AD3A-4b89-841F-09CFE02D16B7}"="Microsoft Visio previewer"
PPT:
"{65235197-874B-4A07-BDC5-E65EA825B718}"="Microsoft App-V Preview Handler for .pptx"
Word：
"{84F66100-FF7C-4fb4-B0C0-02CD7FB668FE}"="Microsoft App-V Preview Handler for .rtf"
整体注册表参考：
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\PreviewHandlers]
"{13D3C4B8-B179-4ebb-BF62-F704173E7448}"="Windows Contact Preview Handler"
"{1531d583-8375-4d3f-b5fb-d23bbd169f22}"="Windows TXT Previewer"
"{53BEDF0B-4E5B-4183-8DC9-B844344FA104}"="Microsoft Windows MAPI Preview Handler"
"{8a7cae0e-5951-49cb-bf20-ab3fa1e44b01}"="Windows Font previewer"
"{92dbad9f-5025-49b0-9078-2d78f935e341}"="Microsoft Windows Mail Mime Preview Handler"
"{a42c2ccb-67d3-46fa-abe6-7d2f3488c7a3}"="Windows RTF Previewer"
"{b9815375-5d7f-4ce2-9245-c9d4da436930}"="Microsoft Windows Mail Mime Preview Handler"
"{BFD468D2-D0A0-4bdc-878C-E69C2F5B435D}"="Microsoft Windows Mail Html Preview Handler"
"{E64164EB-1AE0-4C50-BAEF-A413C2B3A4BC}"="Microsoft 3MF Shell Thumbnail and Preview Handler"
"{f8b8412b-dea3-4130-b36c-5e8be73106ac}"="Microsoft Windows Mail Html Preview Handler"
"{031EE060-67BC-460d-8847-E4A7C5E45A27}"="Windows Media Player Rich Preview Handler"
"{FFBD7029-84D7-4E1E-BE44-B6619BC545ED}"="Foxit PDF Preview Handler"
"{1B96FAD8-1C10-416E-8027-6EFF94045F6F}"="Foxit PDF Preview Provider (XP)"
"{84F66100-FF7C-4fb4-B0C0-02CD7FB668FE}"="Microsoft App-V Preview Handler for .rtf"
"{65235197-874B-4A07-BDC5-E65EA825B718}"="Microsoft App-V Preview Handler for .pptx"
"{21E17C2F-AD3A-4b89-841F-09CFE02D16B7}"="Microsoft Visio previewer"
"{00020827-0000-0000-C000-000000000046}"="Microsoft App-V Preview Handler for .xltx"