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Calendar times are shifted one hour when sent to Google Calendar

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I am running TB 102.9.0 and use Provider for Google Calendar to sync my calendar with my other devices. Information that I receive from Google Calendar is correct, but any entry that I add to my computer has been shifting by one hour since daylight savings started. I have checked the timezone settings on my computer and in Google Calendar and all are correct. I tried deleting my Google Calendar subscription from TB and adding it back, but everything is still off by one hour. What more can I try?

I am running TB 102.9.0 and use Provider for Google Calendar to sync my calendar with my other devices. Information that I receive from Google Calendar is correct, but any entry that I add to my computer has been shifting by one hour since daylight savings started. I have checked the timezone settings on my computer and in Google Calendar and all are correct. I tried deleting my Google Calendar subscription from TB and adding it back, but everything is still off by one hour. What more can I try?

Chosen solution

I'm in the UK.

Windows 10 OS Q: What OS are you using ?

computer - Date & time selected Set automatically selected 'Adjust for daylight saving time automatically' Computer timezone: (UTC+00:00) Dublin, Edinburgh. Lisbon, London.

Q: What settings do you have on computer in 'Date & Time'

In Thunderbird: Provider for Google Calendar version : 102.0.3 Q : are you using same version?

Settings > Calendar Timezone: Europe/London Q: what setting is selected in your Settings > Calendar?

In Thunderbird calendar - gmail calendar

first stage of check: Created a simple event on 7th April time 2pm - 3pm Checked each 'Day, Week, Multi-week, Month' Event info says 2pm-3pm 'Day' selected and it shows event in the 2pm-3pm slot. All time slots correctly match the event time.

First stage of checking result : All seems ok.

Second stage of check: Check Google Calendar via Firefox browser. Q: What browser are you using?

'Day' selected and it shows event correctly in the 2pm-3pm slot. Second stage result: all ok.

Please only do those two stages as checks and report each stage, do you have a problem? Note: At this point do NOT try to view anything via a phone.

I'm trying to work out at which point in the process the issue arises and what settings you are using.

Don't have phone so cannot check the next stage to see if phone synchronising with calendar then alters anything in Thunderbird.

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All Replies (3)

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I realized that I needed to add that TB shows the correct time, but the time for the same appointment is shifted by one hour on Google Calendar and is therefore off by one hour on my phone. Yet anything entered on my phone appears with the correct time on TB, so the issue is one directional.

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Chosen Solution

I'm in the UK.

Windows 10 OS Q: What OS are you using ?

computer - Date & time selected Set automatically selected 'Adjust for daylight saving time automatically' Computer timezone: (UTC+00:00) Dublin, Edinburgh. Lisbon, London.

Q: What settings do you have on computer in 'Date & Time'

In Thunderbird: Provider for Google Calendar version : 102.0.3 Q : are you using same version?

Settings > Calendar Timezone: Europe/London Q: what setting is selected in your Settings > Calendar?

In Thunderbird calendar - gmail calendar

first stage of check: Created a simple event on 7th April time 2pm - 3pm Checked each 'Day, Week, Multi-week, Month' Event info says 2pm-3pm 'Day' selected and it shows event in the 2pm-3pm slot. All time slots correctly match the event time.

First stage of checking result : All seems ok.

Second stage of check: Check Google Calendar via Firefox browser. Q: What browser are you using?

'Day' selected and it shows event correctly in the 2pm-3pm slot. Second stage result: all ok.

Please only do those two stages as checks and report each stage, do you have a problem? Note: At this point do NOT try to view anything via a phone.

I'm trying to work out at which point in the process the issue arises and what settings you are using.

Don't have phone so cannot check the next stage to see if phone synchronising with calendar then alters anything in Thunderbird.

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Thanks for your help. The problem was that for some reason, TB's Calendar setting was off by one hour (US Pacific vs Mountain time), which I never changed so I will chalk it up to one of those mysteries of how a one bit change occurs. Unfortunately, changing the setting changed all of the event times posted in TB, so I had to go through and edit all of them to enter the correct time zone. Once that was done and I sync'd everything, the times lined up correctly.