Message text:

After Effects error: Internal verifiaction failure, sorry! {can’t evaluate expr on parentless stream}.

Message interpretation:

An expression could not be evaluated, because it does seem to not belong to any property.

Possible causes:

This message is part of a series of errors (also see this error) triggered by a very specific scenario. In the given case, the user had linked mask shapes across layers using simple pickwhip expressions, a feature which has been introduced in CS4. In addition, he reversed the layer in time, which caused this issue.

Resolution or workaround:

The solution is actually quite obvious: Link the masks, but do so in a separate sub-composition. Then time-reverse that composition when it becomes the layer in the main composition. If that is not possible, avoid the linking of the masks all together and copy&paste the actual data instead.

Message text:

After Effects error: Root should be layer.

Message interpretation:

A function failed, because it could not associate its container element.

Possible causes:

This message is part of a series of errors (also see this error) triggered by a very specific scenario. In the given case, the user had linked mask shapes across layers using simple pickwhip expressions, a feature which has been introduced in CS4. In addition, he reversed the layer in time, which caused this issue.

Resolution or workaround:

The solution is actually quite obvious: Link the masks, but do so in a separate sub-composition. Then time-reverse that composition when it becomes the layer in the main composition. If that is not possible, avoid the linking of the masks all together and copy&paste the actual data instead.

Message text:

After Effects error: Unsafe operation attempted.

Message interpretation:

A code fragment returned an ambiguous result.

Possible causes:

In the specific case, the sampleImage() function was used in combination with other code to retrieve color information. However, no safeguards were put in place to specify the exact coordinates for the color sampling, so it would produce wrong results if the layer was moved.

Resolution or workaround:

If you are uncertain, always add layer space transforms such as .toComp() for such operations. Likewise, when dealing with colors, always make sure to use the correct syntax to conatin all color components in arrays.

Message text:

After Effects warning: Bad method arguments: This property has no keyframe number 0.
Error occurred on line 17.
Expression disabled.

Message interpretation:

You tried to use a function in combination with an invalid value. In this particular example you tried to access a the first keyframe of this property but unlike normal arrays, keyframes are always counted from 1 up, not zero, so the function ended up empty.

Possible causes:

In most cases these are simple mistakes. Either they are typos or you’ve just forgotten the correct syntax.

Resolution or workaround:

Use the correct values for the function.

Message text:

After Effects error: Attempt to get a value from a time stream with no key values.

Message interpretation:

A function that is dependent on keyframed data did not find any.

Possible causes:

Functions such as loopOut() need keyframe data to do what they are supposed to do – extrapolate paramaters beyond the keyframes. Logically, it cannot do so if no keyframes exist to give any clue about interpolation.

Resolution or workaround:

Create at least one keyframe on the property.

Message text:

After Effects warning: Class ‘Property’ has no property or method named ‘ ‘ Expression Disabled.

Message interpretation:

You used an incorrect function or variable name that is not declared. It does not exist and cannot be used.

Possible causes:

In most cases these are simple typos. Other than that some properties and methods that are dependent on specific data structures cannot be applied to all channels. For instance you cannot apply a layer space transform like toComp() to a parameter-only channel. It only works on transform properties like Position.

Resolution or workaround:

Fix the typos and use the correct properties and methods suitable for each parameter.

Message text:

After Effects warning: Expression result must be of dimension 1, not 3.

Message interpretation:

A property or function that only accepts one value was fed with multiple values contained in an array.

Possible causes:

When working with properties that use multiple values on separate dimensions like Position or Scale it is most important to properly separate them for calculations. If this isn’t done, the calculation will either refuse to compute or only use the first value in the array.

Resolution or workaround:

Separate values in arrays by referncing their index.

Example:

For a position triplet of the form XYZ we have three values, lets say 100,200,100. To extract the Y value, we will refer to its index

position[1]

This returns the second value in the collection. Since arrays always start at zero, using the number 1 will be the correct choice.