Split Large PST Files
PST Splitter helps to Split Large Files Easily
Why unable to open attachment in Outlook!

Outlook serves to be one of the best email client application with the complete user friendly tools and menus letting user access as well as process their mails. However likewise any application problem do come up with Outlook applications too and therefore user find issues in opening, deleting, sending or receiving any mails in Outlook.

Likewise sometimes user find tough to open attachment files in Outlook. Outlook latest extension is configured in a way so that certain files are not allowed to be opened and is because of safety purpose as there might be suspicious attachments mails that are sent via emails and while opening such files, can harm the entire processing of Outlook.

Although the settings provided by Microsoft Outlook is for the Outlook mail's security concern however it often creates problem in opening mails those are legitimate and people requiring to open their urgent official attachment suffer problem. If Outlook mail attachment is not being opened because of Outlook default settings then user is directed to follow the instruction given below:-

  • Run Outlook and click the 'menu' and 'Options' tab.
  • Access the security tab and checkmark with labeled texts as “Do not allow attachments to be saved or opened that could potentially be a virus.” is needed to be removed.
  • Further save the settings selecting 'OK' button.

Additionally there are more blocked attachment list that are set as blocked by default and are as below:-

  • .exe
  • .hlp
  • .hta
  • .lnk
  • .msi
  • .mst
  • .vbe
  • .vbs
  • .chm
  • .cmd
  • .com


In case if removing the checkmarks still the user finds unable to open attachments in outlook then it implies serious issue with Outlook pst file. As Outlook is restricted to have the pst file upto certain file size limit and if constant storage of data inside the pst file if exceeds leading to increase beyond the pst size limit then it is seriously harms the pst folder and therefore no mails or attachments can be opened at the moment.


Resolving such large pst file requires to either crop or archive it. Although cropping the pst file content does remove few data from the pst file so as to lessen the pst file size however it does effect a lot. Similarly archiving pst file will remove few attachments from pst folder and thereby result data loss that is not the perfect solution. The most perfect way out to get rid of the large pst file problem is to split pst file so that the oversize Outlook pst file will get divided in smaller pst file size and no data loss too will result there. Hence try out splitting the pst file and then again try to access pst file attachments.


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