Starting from Foxit PDF Editor V2023.2 &V13 and Foxit PDF Reader V2023.2, there is no “Allow Multiple Instances" option. Instead, there is an " Always Open Files in a New Window " option. In the older versions, when multiple instances were allowed, I could open the same document in two different windows and read/compare them side by side. Now it can only open different documents in different windows, but the same document can’t be opened open in new windows. Additionally, if a PDF file crashes in one window, all separate Foxit windows will close simultaneously, unlike previous versions where different windows were unaffected by each other.
Why the option changed：
Previously, the "Allow Multiple Instances" option enabled users to open the same document in two different windows and read/compare them. However, this feature had limitations, such as the inability to combine opened files from different instances. In the updated version, the "Always Open Files in a New Window" option allows users to open multiple files in different windows within the same Foxit instance. This change addresses the issue of combining opened files and enables all documents to be recognized and listed when combining them.
Solutions for users who prefer multiple instances or opening the same PDF file in two separate windows:
- Registry Modification
- Creating a New Copy of the Document
- Using the Split View Feature
If you still prefer to use the "Allow Multiple Instances" feature in your Foxit PDF Editor/Reader,please navigate to the following registry entry:
For Foxit PDF Editor:
HKEY_CURRENT_USER\SOFTWARE\Foxit Software\Foxit PDF Editor \Continuous\Preferences\Documents
HKEY_CURRENT_USER\SOFTWARE\Foxit Software\Foxit PDF Editor\Preferences\Documents
For PDF Reader：
HKEY_CURRENT_USER\SOFTWARE\Foxit Software\Foxit PDF Reader\Continuous\Preferences\Documents
Then, manually create the "bForceMultiInstance" string in the right panel and set its value to 1 as shown in the screenshot below:
Creating a New Copy of the Document
Please create a new copy of your document (e.g., duplicating A.pdf to A_copy.pdf) and open both files in two separate windows.
Using the Split View Feature
Use the "View > Vertically Split / Horizontally Split" feature to display two views of the same document within the same window.