Text disappears or becomes garbled

[Losen]

Sometimes the text of pdf disappear after minimizing pdf xchange editor and maximizing it again when I need.
But all image, comment and highlight still exist, only the text disappear (or sometimes part of text will become garbled.
I need to reopen my pdf file to fix this problem every time it occurs.
It's really annoying to me. How can I fix this permanently?
My environment is Win10 1803 x64
Thanks a lot.

[Daniel - PDF-XChange]

Hello Losen,
Can you please verify that you are up to date and currently running V7.0.325.1.
you can check this by opening the Help > About dialog window from inside the Editor. If you are not, please follow the below instructions to perform a clean reinstallation (be sure to use installers directly from our website at all times, I have included links below).

This method has a few extra steps beyond uninstalling, so please follow them closely, and be sure to Restart the computer at every point it is detailed, this is crucial to the process working.

Please go to: Control Panel\Programs\Programs and Features in your system and uninstall everything that is published by Tracker Software Products
Once this is complete, please restart your computer.
Once restarted, please go to regedit.exe built into every windows computer. Find it by typing "regedit.exe" in search bar of your start menu.
Please delete the following registry entries. Only the "Tracker Software" folder and all its sub-folders. **Be extremely careful as a mistake could render your computer useless**
- HKEY_LOCAL_MACHINE\SOFTWARE\Tracker Software
- HKEY_CURRENT_USER\Software\Tracker Software
You can now close Regedit.
Please make sure there are no Tracker Software folders here: C:\Program Files.
If so, please delete it.
Restart your computer.
Now install the software:
1. Please run the appropriate installer:
- Editor or Editor plus users: https://www.pdf-xchange.com/PDFXVE7.zip
- PDF-XChange PRO users: https://www.pdf-xchange.com/PDFXPro7.zip
2. When asked by the installer, please choose PRO version, then, copy/paste your serial key into the field provided. Be sure to use CTRL+V to paste the key
3. Now complete the installation and restart your PC.