Slimjet 12.0.14.0 is trying to download extension_1_4_8_903.crx without any user request to do so.
This causes serious troubles as the download request is forwarded to BITS-service. BITS cannot execute the job corectly as a 3rd-party Firewall may stop the host-program SVCHOST for the bits service to access port 80 (configured by purpose). This causes the jobqueue of BITS to grow and BITS consistently tries / retries to execute the download job which finally causes a mess.
There is no way to stop SLIMJET to secretly auto-download extensiosn (e.g. PDF . . . . ) The auto-update request is also set to never.