People living in Scotland have spoken of holiday stress and frustration caused by the Scottish government's vaccine certificate system.
Other UK nations use apps which provide a QR code as proof of vaccination, in line with a system used across Europe.
However, people in Scotland have to request a paper certificate sent by post, which countries may not accept.
Travel agents say Scottish travellers have been "blindsided" and in some cases may have to endure quarantines.
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The EU Digital Covid Certificate is available in all 27 member nations - plus Switzerland, Iceland, Norway and Liechtenstein.
Because the UK is no longer in the EU, the certificate is not available to most Britons, leading to a number of problems.
The Scottish government has said it hopes to introduce a digital scheme next month.
French-born Virginie Brouard, who owns the Edinburgh wine bar and restaurant Le De-Vin, travelled to Brittany in France with her children to visit her parents - whom she had not seen in two and a half years.
France has recently rolled out a new health pass which means people need proof of vaccination to enter places such as museums and cinemas.