naps2.sdk - problem with scanner in citrix environment

[tobiasoehler]

Describe the bug

I have tried to access a scanner via redirected Twain in Citrix using the NAPS2.Sdk and the examples. However, the process hangs and the scanner is then blocked via Twain.

Logging in first Scan:

Scanning with ScanDevice { Driver = Twain, ID = PaperStream IP SP-1125, Name = PaperStream IP SP-1125 } Scan source: Duplex; bit depth: Color; dpi: 150; page size: 8.5x11 in Using TWAIN DSM: C:\WINDOWS\twain_32.dll NAPS2.TW - Opening session NAPS2.TW - StateChanged (to 3) NAPS2.TW - Finding source NAPS2.TW - Opening source NAPS2.TW - Name: PaperStream IP SP-1125; Manu: FUJITSU; Family: PaperStr; Version: 3.32 3.32.0.1361 Apr 23 2024; Protocol: 2.4 NAPS2.TW - StateChanged (to 4) NAPS2.TW - Configuring source NAPS2.TW - Enabling source NAPS2.TW - StateChanged (to 5)

-> from here it does not go any further - it hangs

Logging in second Scan:

Scanning with ScanDevice { Driver = Twain, ID = PaperStream IP SP-1125, Name = PaperStream IP SP-1125 } Scan source: Duplex; bit depth: Color; dpi: 150; page size: 8.5x11 in Using TWAIN DSM: C:\WINDOWS\twain_32.dll NAPS2.TW - Opening session NAPS2.TW - StateChanged (to 3) NAPS2.TW - Finding source NAPS2.TW - Opening source NAPS2.TW - Name: PaperStream IP SP-1125; Manu: FUJITSU; Family: PaperStr; Version: 3.32 3.32.0.1361 Apr 23 2024; Protocol: 2.4 NAPS2.TW - Finishing with error Error: NAPS2.Scan.Exceptions.DeviceException: TWAIN error: MaxConnections

• OS: Laptop with Windows 10 accessing Window Server 2019 via Citrix and redirected Twain

Additional context

When using the Naps2 console application and the Naps2 exe, the scanner works without any problems.