Delayed response when a file is on network

[pmthompson]

Description of the Issue

When switching to Notepad++ from another app, there is a 5-15 second delay in response. I.e. when I click back to Notepad++ window from another app, Notepad++ is unresponsive for 5-15 seconds. Some keystrokes are queued; others are dropped. This only seems to happen if I have opened a file from a mapped network share. It doesn't matter if the "active" file in Notepad++ is from a local drive -- ANY file opened by Notepad++ that is on a mapped network share will cause this delay, ALTHOUGH the delay seems to be dependent on the number or size of files opened from a network. If I have opened a single 20 line file from network, there doesn't seem to be a noticeable delay. If I have a 500 line, 400 column listing file open, there is a definite delay.

Steps to Reproduce the Issue

1. Open file on mapped network drive
2. Navigate to another app (browser, PDF viewer, RDP session, Outlook, etc)
3. Click in the Notepad++ windows. There is no response to the keyboard for 5-15 seconds.

Expected Behavior

I expect that when I use the keyboard, Notepad++ will do something.

Actual Behavior

No response from Notepad++ for 5-15 seconds.

Debug Information

Notepad++ v7.5.1 (32-bit)
Build time : Aug 29 2017 - 02:35:41
Path : C:\Program Files (x86)\Notepad++\notepad++.exe
Admin mode : OFF
Local Conf mode : OFF
OS : Windows 10 (64-bit)
Plugins : ComparePlugin.dll HexEditor.dll JSLintNpp.dll mimeTools.dll NppConverter.dll NppExport.dll NPPJSONViewer.dll NppTextFX.dll PluginManager.dll Tidy2.dll XMLTools.dll

More information:
I work remote and connect to company network with Pulse VPNFortiNet FortiClient. Many of the files I edit are on a mapped network drive. As noted, the delay occurs only if Notepad++ has ANY open file is on the network -- not just the "current" file. I've tried renaming "plugins" and that does not eliminate the delay.

The delay isn't present with other apps like Foxit PDF reader if I'm viewing a PDF located on a network drive.