A block on emails to Powys council, intended to protects its computer systems from the ransomware virus, has been lifted.
Organisations across the world were hit by cyber-attacks last Friday which led to the NHS in England being ground to a halt.
To prevent computers in the Welsh NHS becoming infected all incoming emails from outside organisations were deleted from Friday onwards.
As Powys council shares the Welsh NHS email system all emails from outside servers to the council were also delated.
However the council has confirmed the email block was lifted on Thursday, May 18.
A spokesman said: "The precautionary block on external emails to @powys.gov.uk addresses has now been lifted and people outside the network are now able to contact the council via email once more.
"The lockdown was introduced by the council’s email supplier NHS Wales Informatics Service (NWIS) as a precautionary measure following last week’s international cyber attack."
But the council said all emails sent to it from midnight on Thursday, May 11 and 9.30am on Thursday, May 18 have been deleted. It is urging residents to re-send those emails, if still relevant.
The authority also deleted job applications and applications to vote by post or proxy.
Job applications that had closing dates to the end of last week and Wednesday were extended until Sunday, May 21. The council had created a special form during the block to allow people to apply for postal votes online.
"We realise that the disruption caused inconvenience to our residents and partners and we apologise for this. However, it was important that our computer systems remained safe. The council continues to remain vigilant as similar attacks could be made in the future," said the spokesman.