fix another batch of broken links

account/index.markdown

@@ -9,7 +9,7 @@ Please read our [[account policy|policy]] page on how to obtain and extend D-PHY
 
 ## ETH Account
 
-The **ETH Account** (formerly **nethz Account**) is given by the [ETH Rektorat](http://www.rektorat.ethz.ch/) to every student and by [ETH human resources](http://www.pa.ethz.ch/) to every employee at ETHZ. You should get this login and password by regular mail to your home address. Please ask your secretary in case of problems.
+The **ETH Account** (formerly **nethz Account**) is given by the [ETH Rektorat](http://www.rektorat.ethz.ch/) to every student and by ETH human resources to every employee at ETHZ. You should get this login and password by regular mail to your home address. Please ask your secretary in case of problems.
 
 This account is required to access your @ethz.ch (or @student.ethz.ch) [email](https://mail.ethz.ch), the [wireless network](/network/wireless), [VPN](http://www.vpn.ethz.ch), licensed software via [IT Shop](http://itshop.ethz.ch) and several other ETH-wide services. Just to make things even more interesting, there are two passwords associated with each ETH Account: the LDAP/AD password and the Radius password. The following list gives you an idea of which one to use:
 

calendar/how_to_import_webcal_calenders_into_egroupware.markdown

@@ -10,8 +10,3 @@ How to Import WebCal Calenders into eGroupware
   * Choose "import-calendar-ical" as "Definition".
   * Add the webcal URL (with http:// instead of webcal:// if present) as "Ziel" or "Target"
   * Fill in the some cron-like time ranges during which the file should be downloaded, e.g. "minute 0" for "every full hour"
-
-In Case of Import Errors
-------------------------
-
-  * Check the ics file with e.g. http://icalvalid.cloudapp.net/

linux/software_on_the_d-phys_linux_computers.markdown

@@ -192,8 +192,7 @@ Video Editing
 Scientific Software
 -------------------
   * [amide](http://amide.sourceforge.net/)
-  * [cadabra2](https://github.com/kpeeters/cadabra2)
-  * [cadabra](http://cadabra.phi-sci.com/)
+  * [cadabra](https://cadabra.science)
   * [colmap](https://github.com/colmap/colmap)
   * [cloudcompare](http://www.danielgm.net/cc/)
   * [cuba](http://www.feynarts.de/cuba/) on request

services/berufsbildung_modul_it.markdown

@@ -19,7 +19,6 @@ Berufsbildung Modul IT
       * Zahlen, z.B. von http://www.internetworldstats.com/stats.htm
     * Die Sendung mit der Maus: Wie funktioniert das Internet? https://www.youtube.com/watch?v=fpqhjEtznVk
     * Routing: http://de.wikipedia.org/w/index.php?title=Datei:Internet_map_1024.jpg
-    * (Welchen Weg nimmt eine E-Mail? http://www.youtube.com/watch?v=78px6xvpuLk)
   * Technik (30min)
     * Client (Desktop-Rechner, Laptop, Smartphone, aber auch moderne Geraete wie Internetradios, Fernseher)
     * Modem (Analog, DSL, Kabel, Mobilfunk)

services/contact.markdown

@@ -40,7 +40,7 @@ Scheduled group meetings are Monday 1000-1100 and first Thursday of each month 1
 
 #### ...using public transport
 
-  * Use lines 37, 80 or 69 to [ETH Hönggerberg](http://www.vbz.ch/vbz_opencms/opencms/vbz/deutsch/Fahrplan/ZVV-Fahrplan/fahrplan_vbz.html?S=&Z=eth+h%F6nggerberg&Finden.x=0&Finden.y=0&Finden=Finden) or the [direct bus](http://www.ethz.ch/about/location/hoengg/index_EN) from the main station or ETH Zentrum.
+  * Use [VBZ](https://www.stadt-zuerich.ch/vbz) lines 37, 80 or 69 to ETH Hönggerberg or the [direct bus](http://www.ethz.ch/about/location/hoengg/index_EN) from the main station or ETH Zentrum.
   * Go north (towards Affoltern) and turn right after the _Polybuchhandlung_.
   * Enter the _HPT_ building, and go up to the _H_ floor.
   * Look for the office with the _ISG Helpdesk_ sign.

services/using_remoteapp.markdown

@@ -15,7 +15,7 @@ Prerequisite
 **macOS**
 
    * macOS 10.9 or newer
-   * [Remote Desktop Client](https://itunes.apple.com/ch/app/microsoft-remote-desktop/id715768417?mt=12)
+   * [Microsoft Remote Desktop](https://apps.apple.com/us/app/microsoft-remote-desktop/id1295203466)
 
 **linux**