Arma: Data File too short/Arma OA No Entry and Data File too short

[SpennyG98]

Whenever I try to launch Arma 2 I get a
Data File too short 'addons/anims.pbo'. Expected 650211804 B, got 446300160 B
When I try to launch Arma OA I get a
No Entry 'bin/config.bin/CfgInGameUI/MPTable.shadow'.
followed by a
Data File too short 'c:/program files
(86x)/steam/steamapps/common/arma2/addons/anims.pbo'.
Expected 650211804 B, got 446300160 B

[ProfTournesol]

Look at this topic and follow the advice.