Descriptive Problem Summary:
No antivirus installed

Opening BYOND shortcut, or the Dream Maker shortcut or the Dream Daemon shortcut all give the same result - Windows makes a spinning wheel of processing on the cursor which goes away after roughly 5 seconds, but nothing actually happens on the screen after that, not even on the task bar.

Checking CTRL+ALT+DEL Task Manager shows that a new byond.exe *32 process is opened each time the byond link is clicked, and the same result with dreamdaemon.exe *32 and dreammaker.exe *32

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I checked both application log and application error log on https://i.imgur.com/ikgALbs.png but nothing at the times BYOND crashes (I temporarily loaded the latest version to force another 'crash' but yeah nothing.. It's probably to do with as mentioned before it doesn't actually close itself it stays open, it only closes if I go ctrl+alt+del and find byond.exe which I have to do to be able to overwrite it and down-grade byond again)

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I'm wondering if maybe it's related to the horrible bug where popups will stay white for a good thirty seconds to a minute or so because that started recently too (again I did clear the byond folder in user folder as well as wiping everything in byond so I don't know whyyyy) - like the start screen one (set up character, crew manifest, join, observe, show player polls), computers, other player's item removal popup etc

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Numbered Steps to Reproduce Problem:
Opening any of the BYOND shortcuts. Or opening a byond://link from browser or Play Now link from http://www.byond.com/games/exadv1/spacestation13

Expected Results:
Opening BYOND to login or play

Actual Results:
Windows cursor spinning wheel, nothing else shows on screen, not even on the taskbar - Checking CTRL+ALT+DEL shows a new byond.exe in task manager

Does the problem occur:
Every time? Or how often?
Every time
In other games?
Yes, tried other links on http://www.byond.com/games just in case
In other user accounts?
No, weirdly the latest 5.0.512.1442 version works fine on other Windows accounts but anything from 5.0.5.512.1427 and above will not load on normal account even after checking in the user account folder for My Documents\BYOND and deleting it, I don't get what is different between the two? I think in windows the only difference when swapping accounts should be stuff in the C:\users\username\ folder, I don't get why it acts so differently

When does the problem NOT occur?
Using other windows account or using BYOND 5.0.512.1426 or below

Did the problem NOT occur in any earlier versions? If so, what was the last version that worked? (Visit http://www.byond.com/download/build to download old versions for testing.)
5.0.512.1426 works, 1427-1442 doesn't (laboriously tested by going back and experimenting until I found where it stopped working :( )

Workarounds:
Using other windows account or using BYOND 5.0.512.1426 or below