When a web map is saved from a feature layer or feature collection and is printed from the ArcGIS Enterprise map viewer with feature labeling turned on, the labels print with replacement glpyhs (null / empty boxes, or squares). Below is an example of web map printed with labels in Simplified Chinese in ArcGIS Enterprise 10.6:
A certain font is missing on the server where the print service is running. Starting with ArcGIS Enterprise 10.6, the font Arial Unicode MS is required to be installed on the printing server, as printing a web map with correct labels in certain Unicode characters are not supported by the default font, “Arial”.
The following languages are affected but not limited to:
Manually install the font Arial Unicode MS on the server where the print service is running. As the example below shows, the labels in Simplified Chinese are printed correctly if the font is installed.
The ArcGIS Server machine may not have the Arial Unicode MS font if Microsoft Office is not installed; however, these fonts can be installed separately. Arial Unicode MS can be downloaded as part of the International Support features provided by Microsoft. See Microsoft Support for more details on how to install Arial Unicode MS on Windows.