Symptom

The map service "HERE", "MapTiler" or "Bing Maps [aerophoto]" is set as background map but is not shown.

In PTV Visum: Edit graphic parameters -> Background map -> Map service.
The preview returns only the warning:
"Unable to call background map with the current settings.
Background map could not be called by server of the map service used.
Check the parameters of the used map service and your internet connection. The server of the used map service might be temporarily unavailable."

Inserting static Internet maps (Insert mode -> Backgrounds -> Network editor -> (left mouse button) -> Internet maps) from Bing Maps or Open Street Map fails with:
- "Tile 1 could not be created, because one or more partial tiles could not be retrieved from the server of the map service."
- "Could not create tile 1. Error code: -1011"

Cause

The display of the background map or inserting (static) Internet maps is probably prevented by the proxyserver.

Resolution

For current releases of PTV Visum and PTV Vissim:
Usually Visum/Vissim users cannot change the proxy server, therefore the following text might be relevant for your network administrator.

PTV Visum and PTV Vissim deliberately keep no (encrypted) authentication data, but use the operating system settings under:
Control panel -> Internet Options -> Connections -> LAN settings

A) In case a proxy server or firewall limits the internet access:
- The download of PNG and XML files should be allowed.
- Exclude the following URLs from being blocked:

For MapTiler:
https://api.maptiler.com/maps/

For HERE:
https://xserver2.cloud.ptvgroup.com/services/rest/XMap/tile/

For Bing:
1) https://ecn.t0.tiles.virtualearth.net/tiles/
2) https://ecn.t1.tiles.virtualearth.net/tiles/
3) https://ecn.t2.tiles.virtualearth.net/tiles/
4) https://ecn.t3.tiles.virtualearth.net/tiles/
5) https://dev.virtualearth.net/REST/V1/Imagery/Metadata/

Note: Releases from before 2023 use http.

B) Usually settings for the operating system (commonly used by Internet Explorer) rule the abilities to access the internet through a proxyserver. These can be found following:
Control panel -> Internet Options -> Connections -> LAN settings

Either set the proxyserver address and port, or depending on the network policy set the options
"Automatically detect configuration settings"
and/or
"Use automatic configuration script"
with an address to a file called like
"autoproxy.pac"