normal count of archived chats
-1
Operating system: win 10 pro
Version of Telegram Desktop: 1.7.5 beta
Used theme:

happened to me today too, got lot of unread chats, marked them as read and suddenly count was -1.
Edit: now it always count one less, i have 5 unread messages, it shows 4.
Is this occur still now ?
This does still occurr. But since chat folders have been introduced, this is the first time it happened to me.
When reading all chats, the unread counter should decrement until 0 is reached.
When reading all chats, the unread counter is decrementing until -1 is reached.
And some chats cannot be archived as well.
Counter is reset once Telegram has been restarted.
Operating system: Windows 10 Pro _(v10.0.18362.0 [Maj.Min.Bui.Rev])_
Version of Telegram Desktop: _2.0_
Used theme: _Day (Color: #687B98)_

Logs:
[2020.03.31 10:47:36] Launched version: 2000000, install beta: [FALSE], alpha: 0, debug mode: [FALSE], test dc: [FALSE]
[2020.03.31 10:47:36] Executable dir: C:/Users/mya/AppData/Roaming/Telegram Desktop/, name: Telegram.exe
[2020.03.31 10:47:36] Initial working dir: C:/Users/mya/AppData/Roaming/Telegram Desktop/
[2020.03.31 10:47:36] Working dir: C:/Users/mya/AppData/Roaming/Telegram Desktop/
[2020.03.31 10:47:36] Command line: C:\Users\mya\AppData\Roaming\Telegram Desktop\Telegram.exe
[2020.03.31 10:47:36] Executable path before check: C:/Users/mya/AppData/Roaming/Telegram Desktop/Telegram.exe
[2020.03.31 10:47:36] Logs started
[2020.03.31 10:47:36] Connecting local socket to Global\84f86550570a3c23616a2f66329065f1-{87A94AB0-E370-4cde-98D3-ACC110C5967D}...
[2020.03.31 10:47:36] This is the only instance of Telegram, starting server and app...
[2020.03.31 10:47:36] Moved logging from 'C:/Users/mya/AppData/Roaming/Telegram Desktop/log_start0.txt' to 'C:/Users/mya/AppData/Roaming/Telegram Desktop/log.txt'!
[2020.03.31 10:47:36] Opened 'C:/Users/mya/AppData/Roaming/Telegram Desktop/tdata/working' for reading, the previous Telegram Desktop launch was not finished properly :( Crash log size: 416
[2020.03.31 10:47:36] Update Info: MTP is unavailable.
[2020.03.31 10:47:36] App Error: _basePath is empty in writeSettings()
[2020.03.31 10:47:36] Primary screen DPI: 96
[2020.03.31 10:47:36] App Info: reading settings...
[2020.03.31 10:47:36] App Info: reading encrypted settings...
[2020.03.31 10:47:36] Lang Info: Loaded cached, keys: 2654
[2020.03.31 10:47:36] OpenAL Logging Level: (not set)
[2020.03.31 10:47:36] Audio Playback Devices: OpenAL Soft on Speakers/Headphones (Realtek(R) Audio)
[2020.03.31 10:47:36] Audio Playback Default Device: OpenAL Soft on Speakers/Headphones (Realtek(R) Audio)
[2020.03.31 10:47:36] Audio Capture Devices: OpenAL Soft on Microphone Array (Realtek(R) Audio)
[2020.03.31 10:47:36] Audio Capture Default Device: OpenAL Soft on Microphone Array (Realtek(R) Audio)
[2020.03.31 10:47:37] App Info: reading map...
[2020.03.31 10:47:37] App Info: reading encrypted map...
[2020.03.31 10:47:37] App Info: reading encrypted user settings...
[2020.03.31 10:47:37] App Info: encrypted user settings read.
[2020.03.31 10:47:37] App Info: reading encrypted mtp data...
[2020.03.31 10:47:37] MTP Info: read keys, current: 5, to destroy: 0
[2020.03.31 10:47:37] Map read time: 60
[2020.03.31 10:47:37] Export Info: Destroy top bar by controller removal.
[2020.03.31 10:47:37] Window Shadow: 1, 1, 3, 4, 6, 9, 13, 18, 24, 31, 38, 46
[2020.03.31 11:22:44] Audio Info: recreating audio device and reattaching the tracks
[2020.03.31 11:23:13] Audio Info: Closing audio playback device.
[2020.03.31 12:08:41] Streaming Error: Error in avcodec_find_decoder (code: 8, text: Error number 8 occurred).
[2020.03.31 12:08:41] Audio Info: recreating audio device and reattaching the tracks
[2020.03.31 12:08:47] Audio Info: Closing audio playback device.
[2020.03.31 12:08:48] App Info: writing encrypted user settings...
[2020.03.31 12:22:51] Skipping message, because it is already in blocks!
[2020.03.31 13:18:53] Skipping message, because it is already in blocks!
[2020.03.31 13:20:00] Skipping message, because it is already in blocks!
[2020.03.31 13:20:09] Skipping message, because it is already in blocks!
[2020.03.31 13:20:10] Audio Info: recreating audio device and reattaching the tracks
[2020.03.31 13:20:11] Audio Info: Closing audio playback device.
[2020.03.31 13:20:15] Skipping message, because it is already in blocks!
[2020.03.31 13:20:22] Skipping message, because it is already in blocks!
[2020.03.31 13:20:33] Skipping message, because it is already in blocks!
[2020.03.31 13:20:39] Skipping message, because it is already in blocks!
[2020.03.31 13:24:05] Audio Info: recreating audio device and reattaching the tracks
[2020.03.31 13:24:20] Audio Info: Closing audio playback device.
[2020.03.31 13:26:26] Skipping message, because it is already in blocks!
[2020.03.31 13:28:08] Skipping message, because it is already in blocks!
[2020.03.31 13:29:20] App Info: writing encrypted user settings...
[2020.03.31 13:29:26] App Info: writing encrypted user settings...
[2020.03.31 13:30:51] Skipping message, because it is already in blocks!
Hey there!
This issue will be automatically closed in 7 days if there would be no activity. We therefore assume that the user has lost interest or resolved the problem on their own.
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Thanks!
Still?
Most helpful comment
happened to me today too, got lot of unread chats, marked them as read and suddenly count was -1.
Edit: now it always count one less, i have 5 unread messages, it shows 4.